Laboratory Manual for Basic Mechanical Engineering by Dr. Anil Singh Yadav & Prof. Sachin Kumar Nikam

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ENGINEERING
www.lnct.ac.in Year : I Semester : I/II

Prepared By
Prof. (Dr.) Anil Singh Yadav
Prof. Sachin Kumar Nikam
Mechanical Engineering Department
Lakshmi Narain College of Technology (LNCT)

Name : ............................................................Session: ....................................................
Branch : .........................................................Section : ...................................................
Class Roll No. : ...........................................Enrollment No. : .....................................

LNCT | LNCP | LNCTE | MBA | MCA | LNCT & S



For First Year Engineering Degree Students

Laboratory Manual
for
Basic Mechanical Engineering

Prof. (Dr.) Anil Singh Yadav

Professor
Mechanical Engineering Department
Lakshmi Narain College of Technology Bhopal (M.P.)

Prof. Sachin Kumar Nikam

Assistant Professor
Mechanical Engineering Department
Lakshmi Narain College of Technology Bhopal (M.P.)

This laboratory manual belongs to:

Name: ................................................................Session: .........................................................
Branch: .............................................................Section: ..........................................................
Class Roll No.: .................................................Enrollment No.: ..........................................

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LIST OF EXPERIMETS

S. No. Name of Date of Date of Sign &
1 Experiments Performance Submission Remark

To conduct tensile test on a standard mild
steel specimen with the help of universal
testing machine (UTM).

2 To measure the dimensions of a given
specimen using vernier caliper.

3 To measure the diameter of a given wire
specimen using micrometre.

4 To measure the taper angle of a given taper
specimen using Sine bar.

5 To study of lathe machine.

6 To study of drilling machine.

7 To study of four stroke engines.

8 To study of two stroke engines.

9 To study of simple vertical boiler.

10 To study of Cochran boiler.

11 To study of Lancashire boiler.

12 To study of Locomotive boiler.

13 To study of Babcock and Wilcox boiler.

14 To study of boiler mountings and accessories.

15 To verify Bernoulli's theorem.

iii

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iv

CONTENTS

LIST OF EXPERIMENTS ………………………………………………. iii
v
CONTENTS ………………………………………………. vii
viii
VISION & MISSION ………………………………………………. viii
ix
PROGRAM SPECIFIC OUTCOMES (PSOs) ………………………………………………. x
xi
PROGRAM EDUCATIONAL OBJECTIVES (PEOs) ……………………………………………….

PROGRAM OUTCOMES (POs) ……………………………………………….

LAB OBJECTIVES (LOs) ……………………………………………….

GENERAL LABORATORY SAFETY RULES ……………………………………………….

EXPERIMENT#1 To conduct tensile test on a standard mild steel 1-12
specimen with the help of universal testing machine
EXPERIMENT#2 (UTM).
EXPERIMENT#3 ….................................................................................................
EXPERIMENT#4
EXPERIMENT#5 To measure the dimensions of a given specimen using 13-22
EXPERIMENT#6 vernier caliper.
EXPERIMENT#7 ………………………………………………………………………………
EXPERIMENT#8
EXPERIMENT#9 To measure the diameter of a given wire specimen 23-32
using micrometre.
….................................................................................................

To measure the taper angle of a given taper specimen 33-42
using Sine bar.
….................................................................................................

To study of lathe machine. 43-60
….................................................................................................

To study of drilling machine. 61-74
….................................................................................................

To study of four stroke engines. 75-90
….................................................................................................

To study of two stroke engines. 91-104
….................................................................................................

To study of simple vertical boiler. 105-114
….................................................................................................

v

EXPERIMENT#10 To study of Cochran boiler. 115-124
…................................................................................................. 125-134
135-144
EXPERIMENT#11 To study of Lancashire boiler. 145-154
…................................................................................................. 155-170
171-180
EXPERIMENT#12 To study of Locomotive boiler. 181-184
…................................................................................................. 185-186

EXPERIMENT#13 To study of Babcock and Wilcox boiler.
….................................................................................................

EXPERIMENT#14 To study of boiler mountings and accessories.
….................................................................................................

EXPERIMENT#15 To verify the Bernoulli’s theorem.
…....................................................................................................

BIBLIOGRAPHY ………………………………………………………….………………………

ABOUT THE AUTHORS ……………………………………….……………………………….……..….

vi

vii

VISION & MISSION

Lakshmi Narain College of Technology, Bhopal (MP)

Vision
• To be a premier institute where engineering education and research
converge to produce engineers as responsible citizens.

Mission
• To improve continually in the teaching-learning process by strengthening
infrastructural facilities and faculty credentials.
• To undertake interdisciplinary research and development by engaging the
faculty and students in curricular, co-curricular and industry collaborated
projects towards problem solving.
• To enhance proportion of skilled based courses beyond curriculum to
create more employable graduates.
• To inculcate human values, ethics, patriotism and responsibility in our
outgoing engineers by providing conducive environment.

Department of Mechanical Engineering

Vision
• To be recognized in academics and research for producing engineers as
responsible citizen who are innovative, choice of employers and able to do
further studies & research.

Mission
• To provide knowledge and skills of Mechanical Engineering to the students.
• To impart quality education to make students competent mechanical
engineer and responsible citizen.
• To provide facilities and environment conducive to grounding scholars for
employability, higher studies and research.
• To prepare its students for successful career in engineering.

vii

PROGRAM SPECIFIC OUTCOMES (PSOs)

PSO1 Knowledge of fundamental and specialised subjects of mechanical
engineering and their application in solution of complex engineering
problems.

PSO2 Design, analysis and synthesis of mechanical engineering systems and their
components to meet the needs of Industry and society with due
consideration of public health, safety and environment.

PSO3 Ability of effective communication with the society and the professionals in
complex mechanical engineering activities through development and
presentation of reports and documents.

PSO4 Knowledge and understanding of mechanical engineering and
management principles to manage engineering projects in
multidisciplinary environment as an individual or a leader.

PROGRAM EDUCATIONAL OBJECTIVES (PEOs)

1. To make the students able of applying knowledge of mathematics, science
and subjects of mechanical engineering in dealing with engineering
problems.

2. To be able to identify and understand real life problems and suitably
design and manufacture, feasible and sustainable mechanical devices and
systems.

3. To be able to carry out the research work in the field of Mechanical
Engineering.

4. To be able to use modern tools and techniques for the efficient working
and meeting challenges of modern society and industry.

viii

PROGRAM OUTCOMES (POs)

Engineering Graduates will be able to:

1. Engineering knowledge: Apply the knowledge of mathematics, science,
engineering fundamentals, and an engineering specialization to the solution of
complex engineering problems.

2. Problem analysis: Identify, formulate, review research literature, and analyze
complex engineering problems reaching substantiated conclusions using first
principles of mathematics, natural sciences, and engineering sciences.

3. Design/development of solutions: Design solutions for complex engineering
problems and design system components or processes that meet the specified needs
with appropriate consideration for the public health and safety, and the cultural,
societal, and environmental considerations.

4. Conduct investigations of complex problems: Use research-based knowledge and
research methods including design of experiments, analysis and interpretation of
data, and synthesis of the information to provide valid conclusions.

5. Modern tool usage: Create, select, and apply appropriate techniques, resources,
and modern engineering and IT tools including prediction and modeling to complex
engineering activities with an understanding of the limitations.

6. The engineer and society: Apply reasoning informed by the contextual knowledge
to assess societal, health, safety, legal and cultural issues and the consequent
responsibilities relevant to the professional engineering practice.

7. Environment and sustainability: Understand the impact of the professional
engineering solutions in societal and environmental contexts, and demonstrate the
knowledge of, and need for sustainable development.

8. Ethics: Apply ethical principles and commit to professional ethics and
responsibilities and norms of the engineering practice.

9. Individual and team work: Function effectively as an individual, and as a member
or leader in diverse teams, and in multidisciplinary settings.

10.Communication: Communicate effectively on complex engineering activities with
the engineering community and with society at large, such as, being able to
comprehend and write effective reports and design documentation, make effective
presentations, and give and receive clear instructions.

11.Project management and finance: Demonstrate knowledge and understanding of
the engineering and management principles and apply these to one’s own work, as a
member and leader in a team, to manage projects and in multidisciplinary
environments.

12.Life-long learning: Recognize the need for, and have the preparation and ability to
engage in independent and life-long learning in the broadest context of
technological change.

ix

LAB OBJECTIVES (LOs)

At the completion of course, the students will be able to:

203.1: Perform tensile testing of metal and estimate mechanical
properties.

203.2: Utilize linear and angular dimensions measuring tools.

203.3: Identify different parts and operations of lathe and drilling
machine.

203.4: Distinguish working and applications of different types of internal
combustion engines and steam boilers.

203.5: Verify Bernoulli's theorem through experiment.

x

GENERAL LABORATORY SAFETY RULES

All students must read and understand the information in this document with regard to
laboratory safety and emergency procedures prior to the first laboratory session. Your
personal laboratory safety depends mostly on YOU. Effort has been made to address
situations that may pose a hazard in the lab but the information and instructions provided
cannot be considered all-inclusive.
Students must adhere to written and verbal safety instructions throughout the academic term.
Since additional instructions may be given at the beginning of laboratory sessions, it is
important that all students arrive at each session on time.
With good judgment, the chance of an accident in this course is very small. Nevertheless,
research and teaching workplaces (labs, shops, etc.) are full of potential hazards that can
cause serious injury and or damage to the equipment. Working alone and unsupervised in
laboratories is forbidden if you are working with hazardous substances or equipment. With
prior approval, at least two people should be present so that one can shut down equipment
and call for help in the event of an emergency.
Safety training and/or information should be provided by a faculty member, teaching
assistant, lab safety contact, or staff member at the beginning of a new assignment or when a
new hazard is introduced into the workplace.

Emergency Response
• It is your responsibility to read safety and fire alarm posters and follow the
instructions during an emergency
• Know the location of the fire extinguisher, eye wash, and safety shower in your lab
and know how to use them.
• Notify your instructor immediately after any injury, fire or explosion, or spill.
• Know the building evacuation procedures.

Common Sense
• Good common sense is needed for safety in a laboratory. It is expected that each
student will work in a responsible manner and exercise good judgment and common
sense. If at any time you are not sure how to handle a particular situation, ask your
Teaching Assistant or Instructor for advice. DO NOT TOUCH ANYTHING WITH
WHICH YOU ARE NOT COMPLETELY FAMILIAR!!! It is always better to
ask questions than to risk harm to yourself or damage to the equipment.

Personal and General laboratory safety
• Never eat, drink, or smoke while working in the laboratory.
• Read labels carefully.
• Do not use any equipment unless you are trained and approved as a user by your
supervisor.
• Wear safety glasses or face shields when working with hazardous materials and/or
equipment.
• Wear gloves when using any hazardous or toxic agent.
• Clothing: When handling dangerous substances, wear gloves, laboratory coats, and
safety shield or glasses. Shorts and sandals should not be worn in the lab at any time.
Shoes are required when working in the machine shops.
• If you have long hair or loose clothes, make sure it is tied back or confined.

xi

• Keep the work area clear of all materials except those needed for your work. Coats
should be hung in the hall or placed in a locker. Extra books, purses, etc. should be
kept away from equipment that requires air flow or ventilation to prevent overheating.

• Disposal - Students are responsible for the proper disposal of used material if any in
appropriate containers.

• Equipment Failure - If a piece of equipment fails while being used, report it
immediately to your lab assistant or tutor. Never try to fix the problem yourself
because you could harm yourself and others.

• If leaving a lab unattended, turn off all ignition sources and lock the doors.
• Never pipette anything by mouth.
• Clean up your work area before leaving.
• Wash hands before leaving the lab and before eating.

Electrical safety
• Obtain permission before operating any high voltage equipment.
• Maintain an unobstructed access to all electrical panels.
• Wiring or other electrical modifications must be referred to the Electronics Shop or
the Building Coordinator.
• Avoid using extension cords whenever possible. If you must use one, obtain a heavy-
duty one that is electrically grounded, with its own fuse, and install it safely.
Extension cords should not go under doors, across aisles, be hung from the ceiling, or
plugged into other extension cords.
• Never, ever modify, attach or otherwise change any high voltage equipment.
• Always make sure all capacitors are discharged (using a grounded cable with an
insulating handle) before touching high voltage leads or the "inside" of any equipment
even after it has been turned off. Capacitors can hold charge for many hours after the
equipment has been turned off.
• When you are adjusting any high voltage equipment or a laser which is powered with
a high voltage supply, USE ONLY ONE HAND. Your other hand is best placed in a
pocket or behind your back. This procedure eliminates the possibility of an accident
where high voltage current flows up one arm, through your chest, and down the other
arm.

Mechanical safety
• When using compressed air, use only approved nozzles and never directs the air
towards any person.
• Guards on machinery must be in place during operation.
• Exercise care when working with or near hydraulically- or pneumatically-driven
equipment. Sudden or unexpected motion can inflict serious injury.

Additional Safety Guidelines
• Never do unauthorized experiments.
• Never work alone in laboratory.
• Keep your lab space clean and organized.
• Do not leave an on-going experiment unattended.
• Always inform your instructor if you break a thermometer. Do not clean mercury
yourself!!
• Never taste anything. Never pipette by mouth; use a bulb.
• Never use open flames in laboratory unless instructed by TA.

xii

• Check your glassware for cracks and chips each time you use it. Cracks could cause
the glassware to fail during use and cause serious injury to you or lab mates.

• Maintain unobstructed access to all exits, fire extinguishers, electrical panels,
emergency showers, and eye washes.

• Do not use corridors for storage or work areas.
• Do not store heavy items above table height. Any overhead storage of supplies on top

of cabinets should be limited to lightweight items only. Also, remember that a 36"
diameter area around all fire sprinkler heads must be kept clear at all times.
• Areas containing lasers, biohazards, radioisotopes, and carcinogens should be posted
accordingly. However, do not post areas unnecessarily and be sure that the labels are
removed when the hazards are no longer present.
• Be careful when lifting heavy objects. Only shop staff may operate forklifts or cranes.
• Clean your lab bench and equipment, and lock the door before you leave the
laboratory.

xiii

xiv

A univerrssaall testtiinngg maacchhiinnee (UTTMM)),,
aallssoo kknnoowwnn aass aa uunniivveerrssaall tteesstteerr,,
tmmesaattteefrrriaaiamlslset,esitsitneugssteimndagctohintemestaocrthhmeinaetteenrisaiollesr
smtraetnegrtihalsantdestcofmrapmrees,siivse ussterdengtothteosft
mthaetetreianlssi.leAsntreeanrlgiethr naanmdecfoomr aprteenssilvee
tsetsrteinnggthmacohfinme aisteraiatlesn.soAmneteer.arTliheer
"universal" part of the name reflects
tnhaamt eitfocrana tepnersfiolermtestminagnymasctahnidnaerdis
taentseinlesomanedter.coTmhepre"susnioivnersteasl"ts paornt
mofatetrhieals,nacmomeporneeflnetcst,santdhasttruicttucraesn
(in other words that it is versatile)
perform many standard tensile and
compression tests on materials,
components, and structures (in other
words, that it is versatile).

Universal Testing
Machine (UTM)

Experiment# 1

Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

1 EXPERIMENT NO. 1

Universal Testing Machine Universal Testing Machine (UTM)

AIM
To conduct tensile test on a standard mild steel specimen with the help
of universal testing machine (UTM).

APPARATUS
Universal testing machine, micrometre, extensometer, vernier caliper,
centre punch, 1/4 kg hammer and test specimen.

THEORY
Prior to the design of a machine component, there is a need to
determine the mechanical properties which describe the behaviour of
the material when in use. These properties include:

• Strength is the ability of the material to resist stress without
failure and it is prescribed by ultimate stress.

• Elasticity is the property by virtue of which the entire strain
produced in the material by a stress disappears when the stress
is removed: It is prescribed by the modulus of elasticity which
is the ratio of stress to strain within the range of elastic
deformation.

• Ductility of a material allows it to be drawn out by tension to
smaller section. For example, a wire is made by drawing out
metal through a hole. The lack of ductility is called brittleness.
The percentage elongation and percentage reduction in area
provide a measure for the ductility of a material.

• Malleability of a material enables it to undergo great change in
shape under compressive stress without rupture.

UNIVERSAL TESTING MACHINE (UTM)-CONSTRUCTION
AND WORKING

The tensile test for determining the yield stress, ultimate tensile
strength, breaking stress percentage elongation and percentage
reduction in area of a given specimen is conducted on a universal
testing machine (UTM). This hydraulically operated machine
essentially consists of two main units namely the loading (straining)
unit and the control panel. The control panel is located on the right and
comprises an oil sump, a positive displacement pump run by the
electric motor, load dial indicator and control buttons. A zero-
adjustment knob is provided to set the pointer on load dial to zero
value. The right-side control button operates the flow control valve
while the left one regulates the return valve. The rate of load can be
adjusted by the flow control valve (Fig. 1.1).

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 1

Universal Testing Machine Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

The loading unit, located on the left, has upper, middle and lower
cross heads. The control panel and the loading unit are connected by
pipes through which oil flows under pressure to the hydraulic
cylinder of the loading unit. When in operation, the hydraulic system
draws down the central crosshead. Obviously then a specimen
gripped between the central and upper crosshead is loaded in tension.
For compression test, the specimen is placed on the bottom crosshead
while the middle one is made to move down.

A typical UTM is specified by the following parameters:
• Load capacity
• Overall dimensions (length x breadth x height)
• Ram stroke
• Power supply

Figure 1.1 Universal Testing Machine

Test Specimen: The test-specimen for the tensile test is made in
accordance with certain standards and is usually of configuration
shown in Fig. 1.2.

Figure 1.2 Test specimen for tensile test Universal Testing
Machine

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 2

Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

The grip ends may be cylindrical, pin hole, threaded and shouldered

for gripping it firmly in the fixtures of the machine. The central

portion of the test specimen is somewhat smaller than the end

regions, and this central region constitutes the gauge length over

which elongations are measured. The gauge length is empirically

taken to be

l = 5.65√ ≈ 5 for a circular section
= 4√ .
for a rectangular section where

A is the cross-sectional area of

Universal Testing Machine the test specimen.

Stress-strain diagram: The test specimen is gripped firmly between
the jaws of the machine and the applied load is gradually increased in
suitable steps till failure of the specimen occurs. Values of load and
the elongation in the specified/gauge length are observed
simultaneously. Load is indicated on the load dial and for the very
small extensions involved in the initial stages, the elongation is
recorded by an extensometer. After failure, the length of broken
specimen is measured and diameter at section of failure is taken.
These readings are plotted on a graph sheet with the ordinate
representing the stress and the abscissa representing the strain. Stress
is calculated by dividing the load by the original cross-sectional
area of the test specimen. Strain is calculated by dividing the
extension of the gauge length by the original unstrained length.

Figure 1.3 shows the typical behaviour of stress-strain curve for mild
steel specimen.

Figure 1.3 Stress strain curve for mild steel.

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 3

Universal Testing Machine Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

Its salient features are:
• Proportional limit: When the load is increased gradually in
the initial stages, the elongation and hence the strain is
proportional to load and hence to stress. This proportionality,
called Hook's law, extends upto point A and this point is
called proportional limit.
• Elastic limit: Beyond proportional limit, the stress and strain
depart from straight line relationship. The material, however,
still remains elastic upto point B in the sense that it is able to
return to its original form upon removal of load. The
condition at point B is referred to as the elastic limit.
• Yield point: Beyond elastic limit, the material shows
considerable strain even through there is no increase in load or
stress. The material becomes inelastic (strain not recoverable)
and this onset of plastic deformation is called the yielding of
material. Yielding pertains to the region C-D and there is drop
in load at the point D. The point C is called the upper yield
point and point D is the lower yield point.
• Tensile (ultimate) and breaking strength: After yielding,
the material becomes strain hardened (strength of specimen
increases) and an increase in load is required to take the
material to its maximum stress at point E. The stress at this
point is known as ultimate or the tensile stress of the material.
In the portion EF, there is falling off the load (stress) from the
maximum until fracture takes place at F. The point F is
referred to as the fracture or breaking point and the
corresponding stress is called the breaking stress.

Shape of fracture: For mild steel specimen, the test piece breaks
making a cup and cone type fracture. It may be attributed to the fact
that the tensile specimen fails in shear and the shear stress is
maximum at 45-degree planes with respect to the direction of load.

PROCEDURE

The sequence of operations in the performance of tensile test is
outlined below:

(i) Mark the gauge length on the test specimen and measure
its length.

(ii) Measure the diameter of the gauge length portion by
means of a micrometre atleast at three places and
determine its mean value.

(iii) Fix extensometer (dial gauge) firmly to the test piece and
adjust it to read zero.

(iv) Set the load point at zero by adjusting the initial setting
knob.

(v) Grip the specimen vertically and firmly between the upper
and middle cross-head jaws of the machine.

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 4

Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

Universal Testing Machine (vi) Switch on the machine by pressing the appropriate button
(vii) and apply the load gradually by turning the load valve.
Record the elongation corresponding to each increment of
(viii) load. Continue loading until yield point is reached. This is
(ix) indicated by high values of extension with not much
(x) increase in load. At this stage, remove the diameter and
there after note the changes in length by a linear scale.
(xi) Continue loading and note down the elongation until the
specimen breaks. Note down the breaking load.
Unload the machine by turning the load valve in the
opposite direction.
Remove broken pieces from the jaws of machine. Join
these pieces together and measure the extended final
length between the gauge points and the reduced diameters
at the broken ends, i.e., where the neck is formed. Observe
and sketch the nature of fracture, i.e., the shape of
fractured ends.
Draw the stress-strain diagram after making the necessary
calculations.

OBSERVATIONS

• Specimen prepared from, MS/CI/Al bar

• Original diameter, do = -------------- mm

• Original gauge length, lo (=5xdo) =--------------------------- mm

• Original cross-sectional area of the specimen,

Ao= 2 =-------------------------- mm2
4

• Final gauge length obtained after fracture, Lf =-------------mm

• Final diameter obtained after fracture, df =----------------- mm

• Final cross-sectional area obtained after fracture,

Af= 2 =------------------------ mm2
4

• Yield load, Py =--------------------------N

• Ultimate load, Pu =-----------------------N

• Fracture load, Pf =------------------------N

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 5

Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

OBSERVATION TABLE

Sr. Load Extension Stress Strain
No. applied δl (mm) σ=F/Ao (N/mm2) ε=δl/lo
F (N)

1

2

3

Universal Testing Machine 4

5

6

7

8

9

10

11

12

13

14

15

RESULTS

1. Calculate stress and strain for every interval of applied load in
the observation table.

2. Draw stress-strain curve with the help of observation table.

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 6

Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

3. Compute the following;

• Modulus of elasticity: N/mm2

E= Stress/strain

(obtained from the graph)

• Yield stress (σy): σy= Py/ Ao N/mm2

Universal Testing Machine • Ultimate tensile stress: N/mm2
σu= Pu/ Ao

• Breaking/Fracture stress: N/mm2
Engineering breaking/fracture stress
σf= Pf/ Ao

• True breaking/fracture stress N/mm2
σf= Pf/ Af

• Percentage elongation in length:
% Elongation= [(lf-lo)/lo] x100

• Percentage reduction in area:
% Reduction = [(Ao-Af)/Ao] x100

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 7

Universal Testing Machine Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

PRECAUTIONS

(i) The test-specimen should have uniform cross-sectional
area and surface finish.

(ii) The gauge length portion of the test piece should be free
from any scratch marks.

(iii) To avoid stress concentration and failure at the junction of
the end grip portion and the gauge length, the transitional
change in geometry of the test specimen should be through
a fillet of appropriate radius.

(iv) Gripping of the test piece in the jaws of the machine
should be perfect. Improper gripping would result in
incorrect measurement of rise in load and elongation.

(v) Ensure that the load is applied axially and gradually.

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Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

REVIEW QUESTIONS

Questions for Viva-Voce Q1. What is difference between force and load.
Q2. Define tensile and compressive stress
Q3. Define shear stress.
Q4. Define longitudinal, lateral (transverse) and volumetric strain.
Q5. What do you mean by plastic stage?
Q6. Define Yield point.
Q7. What is the Purpose of UTM?
Q8. Differentiate between ultimate stress and breaking stress.
Q9. What kind of fracture has occurred in tensile specimen?
Q10. The ultimate tensile stress of mild steel compared to ultimate
compressive stress is……..

WRITE YOUR ANSWERS HERE
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Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 9

Questions for Viva-Voce Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

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Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 10

Questions for Viva-Voce Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

MULTIPLE CHOICE QUESTIONS (✔)

Q1. Tensile test can be performed on
a. Impact testing machine
b. Universal testing machine
c. Rockwell tester
d. Brinell tester

Q2. Which machine records the change in length of specimen?
a. Impact testing machine
b. Universal testing machine
c. Rockwell tester
d. Brinell tester

Q3. The ability of the material to resist stress without failure is
called
a. Strength
b. Hardness
c. stiffness
d. toughness

Q4. In universal testing machine, for a circular section specimen,
the gauge length is taken to be
a. 3.65 (A)^1/2
b. 4.65 (A)^1/2
c. 5.65 (A)^1/2
d. 6.65 (A)^1/2
Where A=Area of cross section of the test specimen

Q5. In universal testing machine, the tensile specimen of mild
steel fails in shear and the shear stress is maximum at ………
degrees planes with respect to the direction of load.
a. 30
b. 45
c. 60
d. 75

Q6. What is meant by resilience in stress strain curve?
a. area in the plastic region
b. area in the elastic region
c. area in elastic and plastic region
d. none of the above

Q7. What is meant by ductility?
a. Metals can be drawn into sheets
b. Metals undergo elastic deformation under tensile loads
c. Metals undergo plastic deformation under tensile loads
d. All of the above

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 11

Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

Q8. Up to which point in the graph shown below, Hooke's Law is
obeyed?
a. Up to point D
b. Up to point A
c. Up to point B
d. Up to point E

Questions for Viva-Voce Q9. At which point elastic limit is observed in stress strain curve
shown below
a. Point B
b. Point D
c. Point A
d. None of the above

Q10. Stress strain curve is shown below. Beyond point B, metal
undergoes
a. less elastic deformation and more plastic deformation
b. only elastic deformation
c. more elastic deformation and less plastic deformation
d. only plastic deformation

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 12

A Vernier Caliper is an instrument
for making very accurate
measurements, introduced in 1631
by Pierre Vernier of France. When a
AcoVmepronnieernCt ahlaipsetroibseanmienasstururmedentot ftohre
misnetacrkooidnnudgcevpdelraiyncea1c6oc3uf1radbteyecmiPmieeaarlsr,eureVVmeerrennnitieser,r
oCfaFlirpaenrcse.isWemhepnloayecdo.mponent has to
be measured to the second place of
decimal, Vernier Calipers is employed.

Vernier Caliper

Experiment# 2

Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

2 EXPERIMENT NO. 2

Vernier Caliper Vernier Caliper

AIM
To measure the dimensions of a given specimen using Vernier caliper.

APPARATUS
Vernier caliper, micrometre and rectangular object.

THEORY
A measuring instrument is any device that may be used to obtain a linear
(dimension) or angular measurement. Measurement systems are mainly
used in industries for quality control management. Often quality control
engineers are applying some the measuring systems such as linear and
angular measurements. These measurements are very much useful to
compare the actual measurements with already existing standard
measurements.
The linear measurement includes the measurement of lengths, width,
diameters, heights and thickness. The basic principle of linear
measurement is that of comparison with standard dimensions on a
suitably engraved instrument or device. The various devices used for
measuring the linear measurements are:
(A) Non-precision instruments

• Steel rule
• Calipers
• Dividers
• Telescopic gauge
• Depth gauge
(B) Precision instruments
• Micrometres (screw gauge)
• Vernier calipers
• Vernier depth gauges
• Vernier height gauges
• Slip gauges
(C) Comparators
(D) Coordinate measuring machines

VERNIER CALIPERS

Description of the Vernier caliper
A Vernier caliper is an instrument for making very accurate
measurements, introduced in 1631 by Pierre Vernier of France. When a
component has to be measured to the second place of decimal, Vernier
Calipers and micrometres are employed.

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 13

Vernier Caliper Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

Vernier caliper is one of the common instruments in which the small
measured distance is magnified by an auxiliary (vernier) scale. One scale
(main scale) is fixed and the other scale (Vernier Scale) is sliding on the
main scale. When the zero on the Vernier Scale coincides with the zero
on the main scale, the number of divisions on the Vernier Scale is one
more or one less than the number of divisions on main scale with which it
coincides exactly.
It uses two scales one fixed and the other movable, then the difference
between these two scales can be utilized, to enhance the accuracy of
measurement.

Figure 2.1 Vernier Caliper

• It consists of two scales which can slide along each other, named
as main scale and vernier scale.

• Main scale is the scale which is engraved on solid L-shaped
frame. This scale is divided into 20 parts with centimetre system
so that small division equals to 0.05 cm.

• Vernier scale slides over the main scale and has a movable jaw
which can slide over the frame. With the help of locking nut, the
movable jaw can be locked at any required position.

• The component to be measured is kept between the external jaws
for measuring outer dimensions and between the internal jaws for
measuring inner dimensions.

• To obtain the reading, the number of divisions on main scale are
first read off and then the vernier scale is examined to determine
which of the division coincides or most coincident with a division
on a main scale.

• The fine adjustment can be done by using adjustment screw.

Principle
The difference in the magnitude of one main scale division (M.S.D.) and
one vernier scale division (V.S.D.) is called the least count of the
instrument, as it is the smallest distance that can be measured using the
instrument.

n V.S.D. = (n – 1) M.S.D.

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 14

Vernier Caliper Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

Formulas used
• Least count of vernier calipers =
the magnitude of the smallest division on the main scale
the total number of small divisions on the vernier scale

Verniers with least count of 0.02 mm, 0.05 mm and 0.1 mm are also
available as per the requirement.

PROCEDURE

1. Keep the jaws of Vernier Caliper closed. Observe the zero mark of the
main scale. It must perfectly coincide with that of the vernier scale.

2. Look for the division on the vernier scale that coincides with a
division of main scale. Use a magnifying glass, if available and note the
number of divisions on the Vernier scale that coincides with the one on
the main scale. Position your eye directly over the division mark so as to
avoid any parallax error.

3. Gently loosen the screw to release the movable jaw. Slide it enough to
hold the workpiece lengthwise gently (without any undue pressure) in
between the lower jaws AB. Now, gently tighten the screw so as to clamp
the instrument in this position to the body.

4. Carefully note the position of the zero mark of the vernier scale
against the main scale. Usually, it will not perfectly coincide with any of
the small divisions on the main scale. Record the main scale division just
to the left of the zero mark of the vernier scale.

5. Start looking for exact coincidence of a vernier scale division with
that of a main scale division in the vernier window from left end (zero) to
the right. Note its number (say) N, carefully.

6. Multiply 'N' by least count of the instrument and add the product to
the main scale reading noted in step 4. Ensure that the product is
converted into proper units (usually cm) for addition to be valid.

7. Repeat steps 3-6 to determine the other dimensions (breadth b and
height h) by holding the rectangular block in proper positions. Take three
sets of reading in each case.

8. Record the observations for length, breadth and height of the
rectangular block in tabular form with proper units and significant
figures. Apply zero corrections wherever necessary.

9. Find out the arithmetic mean of readings taken for length, breadth and
height separately.

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 15

Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

OBSERVATIONS

Least count of Vernier Calipers (Vernier Constant)

1 main scale division (MSD) =1 mm = 0.1 cm

Number of vernier scale divisions, N =50 (say)

50 vernier scale divisions = 49 main scale divisions

1 vernier scale division = 0.98 main scale division

Vernier constant = main scale division– 1 vernier scale division

= (1– 0.98) main scale divisions

= 0.02 main scale division

Vernier constant (Vc) = 0.02mm = 0.002cm

Alternatively,
Vernier constant (Vc) = 1 MSD/N=1mm/50=0.02mm=0.002cm

OBSERVATION TABLE

Vernier Caliper Dimensions S. Main Number Vernier Measured
No. Scale of scale dimension
reading,
coinciding reading, =M + V
M vernier V=N× (cm/mm)
(cm/mm) division,
N Vc L1=
(cm/mm)
L2=
1
L3=
Length 2
(L) 3

Breadth 1 B1=
(B) 2 B2=
3 B3=

Height 1 H1=
(H) 2 H2=
3 H3=

CALCULATIONS = [L1+L2+L3]/3=
Mean measured length =……….…....cm

Mean measured breadth =[B1+B2+B3]/3=
=……..…..….cm

Mean measured height =[H1+H2+H3]/3=
=………....….cm

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 16

Vernier Caliper Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

RESULTS
Dimensions of the given rectangular block are:

Length, L =……………cm
Breadth, B =……………cm
Height, H =……………cm
PRECAUTIONS
1. If the vernier scale is not sliding smoothly over the main scale,
apply machine oil/grease.
2. Screw the vernier tightly without exerting undue pressure to
avoid any damage to the threads of the screw.
3. Keep the eye directly over the division mark to avoid any error
due to parallax.
4. Note down each observation with correct significant figures and
units

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 17

Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

REVIEW QUESTIONS

Questions for Viva-Voce Q1. What is the formula for least count?
Q2. What is the function of strip in vernier caliper?
Q3. What is the use of vernier caliper?
Q4. What is the principle of vernier caliper?
Q5. What are the parts of a vernier caliper?
Q6. What is main scale in vernier caliper?
Q7. What is Vernier constant?
Q8. What is a scale division?
Q9. What is a zero error?
Q10. Draw free hand neat sketch of vernier caliper.

WRITE YOUR ANSWERS HERE
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Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 18

Questions for Viva-Voce Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

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Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 19

Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

MULTIPLE CHOICE QUESTIONS (✔)

Q1. Precision of Vernier calipers is
a) 1 mm
b) 1 cm
c) 0.1 mm
d) 0.1 cm

Questions for Viva-Voce Q2. Range of Vernier calipers is
a) 1 cm to 10 cm
b) 1 cm to 5cm
c) 1 cm to 6 cm
d) 1 cm to 20 cm

Q3. A workman measures, as accurately as possible, the length and
internal diameter of a straight copper pipe. The length is
approximately 600 cm and the internal diameter is approximately
2 cm. What is the best combination of instruments for the
workman to use?

INTERNAL DIAMETER LENGTH

A Ruler Ruler
B Ruler Tape
C Vernier Calipers Ruler
D Vernier Calipers Tape

a) A
b) D
c) C
d) B

Q4. The dimensions of a small book is measured as 32.2 mm, 54.2
mm, 13.7 mm. What measuring tool could have been used to
obtain these readings?
a) Vernier Caliper
b) Measuring Tape
c) Meter Rule
d) Micrometer Screw Gauge

Q5. To measure shorter lengths with their accurate reading we use
a) Measuring tapes
b) Meter ruler
c) Vernier caliper
d) All of them

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 20

Questions for Viva-Voce Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

Q6. When using a measuring cylinder, one precaution to take is to
a) obtain more readings by looking from more than one direction
b) look at the meniscus from below the level of the water surface
c) check for the zero error
d) position the eye in line with the base of the meniscus

Q7. Vernier caliper helps in measuring
a) External diameter
b) Internal diameter
c) Thickness and depth of narrow tubes
d) All of them

Q8. The diagram shows part of a vernier scale.

What is the correct reading?
a) 42.5 mm
b) 33.5 mm
c) 38.0 mm
d) 30.5 mm
Q9. What is the zero error as shown in the figure below?

a) 0.03 mm
b) 0.3 mm
c) -0.03 mm
d) -0.3 mm

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 21

Questions for Viva-Voce Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

Q10. The diagram shows part of a vernier scale. What is the reading on
the vernier scale?
a) 3.50 cm
b) 7.00 cm
c) 6.55 cm
d) 7.45 cm

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 22

A micrometer, sometimes known as
Aa mmicicrormometeetre,rsomscerteiwmesgkanuogwe,n iass aa
micrometer screw gauge, is a device
idnecvoircpeoraitnincgorpoaraticnaglibraatecdalibsrcaretewd
wscirdewly wiudseelyd usfeodr foracaccucruarteate linneeaarr
mmeeaassuurreemmenent t ooff ccoommppoonneenntsts iinn
ammseeccwhhaeanlnlicicaaalslenmgoinsteeenmrginiengcehaeanrndiincmgalacthriandaiennsgd,
amloancghininwgith as othewrell meatsrologmicoaslt
imnsetcruhmaneinctasl sturcahdeass, dailaoln, gvewrnitiher,otahnedr
dmigeittraol lcoagliicpaelrs. instruments such as
dial, vernier, and digital calipers.

Micrometer/Screw
Gauge

Experiment# 3

Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

3 EXPERIMENT NO. 3

Micrometre/ Screw Gauge Micrometre/ Screw Gauge

AIM
To measure the diameter of a given wire specimen using micrometre.

APPARATUS
Micrometre and wire specimen.

THEORY
A measuring instrument is any device that may be used to obtain a linear
(dimension) or angular measurement. Measurement systems are mainly
used in industries for quality control management. Often quality control
engineers are applying some the measuring systems such as linear and
angular measurements. These measurements are very much useful to
compare the actual measurements with already existing standard
measurements.
The linear measurement includes the measurement of lengths, width,
diameters, heights and thickness. The basic principle of linear
measurement is that of comparison with standard dimensions on a
suitably engraved instrument or device. The various devices used for
measuring the linear measurements are:
(A) Non-precision instruments

• Steel rule
• Calipers
• Dividers
• Telescopic gauge
• Depth gauge
(B) Precision instruments
• Micrometres (screw gauge)
• Vernier calipers
• Vernier depth gauges
• Vernier height gauges
• Slip gauges
(C) Comparators
(D) Coordinate measuring machines

MICROMETRE/ SCREW GAUGE

Description of the Micrometre/ Screw Gauge

With Vernier Callipers we are usually able to measure length accurately
up to 0.1 mm. More accurate measurement of length, up to 0.01 mm or
0.005 mm, may be made by using a screw gauge. As such a Screw Gauge
is an instrument of higher precision than a Vernier Callipers.

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 23

Micrometre/ Screw Gauge Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

Figure 3.1 Micrometre/ Screw Gauge
A micrometre (Fig. 3.1) mainly consists of following parts:
U-shape frame: It is made of steel or cast iron and holds all parts of
micrometre. The gap between the two ends of U-shape frame allows
maximum size of a component to be measured.
Anvil and spindle: The one end of spindle is attached to thimble and
another end constitutes the movable anvil. Anvil is rigidly fixed to the
one end of frame. As the spindle touch the anvil, thimble cannot be
rotated further in forward direction. When anvil and spindle ends are
brought together the micrometre reads zero.
Thimble: The movement of spindle in forward or backward direction is
controlled by the rotation of thimble. It has 50 equal divisions around its
circumference.
Barrel: It is accurately divided and clearly marked in 0.5 mm division
along its length which acts as a main scale.
Ratchet: It is provided at the end of spindle. It controls the pressure
applied on a component for accurate measurement. When the spindle
reaches near the component, the operator uses the ratchet screw to tighten
the thimble. When the correct pressure is applied, the ratchet
automatically slips and prevents the application of too much pressure.
Lock nut: It is provided on the spindle to lock it when the micrometre is
at its correct reading.

Figure 3.2 Micrometre/ screw gauge

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 24

Micrometre/ Screw Gauge Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

Fig. 3.2 shows a different type of a screw gauge. It has a screw ’S’ which
advances forward or backward as one rotates the head C through rachet
R. There is a linear scale ‘LS’ attached to limb D of the U frame. The
smallest division on the linear scale is 1 mm (in one type of screw gauge).
There is a circular scale CS on the head, which can be rotated. There are
100 divisions on the circular scale. When the end B of the screw touches
the surface A of the stud ST, the zero marks on the main scale and the
circular scale should coincide with each other

Taking the linear scale reading
The mark on the linear scale which lies close to the left edge of the
circular scale is the linear scale reading. For example, the linear scale
reading as shown in Fig. 3.3, is 0.5 cm.

Taking circular scale reading
The division of circular scale which coincides with the main scale line is
the reading of circular scale. For example, in the Fig. 3.3, the circular
scale reading is 2.

Figure 3.3 linear and circular scale reading

Total reading = linear scale reading +
Total reading circular scale reading × least count
(according to the specification of the screw
gauge)
= 0.5 + 2 × 0.001
= 0.502 cm

PRINCIPLE

Micrometre works on the principle of screw and nut. The linear distance
moved by the screw is directly proportional to the rotation given to it. The
linear distance moved by the screw when it is rotated by one division of
the circular scale, is the least distance that can be measured accurately by
the instrument. It is called the least count of the instrument.

Least count =pitch/No. of divisions on circular scale

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 25

Micrometre/ Screw Gauge Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

For example, for a screw gauge with a pitch of 1mm and 100 divisions on
the circular scale. The least count is

1 mm/100 = 0.01 mm
This is the smallest length one can measure with this screw gauge.

In another type of screw gauge, pitch is 0.5 mm and there are 50 divisions
on the circular scale. The least count of this screw gauge is 0.5 mm/50 =
0.01 mm.
Note that here two rotations of the circular scale make the screw to
advance through a distance of 1 mm. Some screw gauge has a least count
of 0.001 mm (i.e. 10-6 m) and therefore are called micrometre screw.

PROCEDURE

1. Take the screw gauge and make sure that the rachet R on the head
of the screw functions properly.

2. Rotate the screw through, say, ten complete rotations and observe
the distance through which it has receded. This distance is the
reading on the linear scale marked by the edge of the circular
scale. Then, find the pitch of the screw, i.e., the distance moved
by the screw in one complete rotation. If there are n divisions on
the circular scale, then distance moved by the screw when it is
rotated through one division on the circular scale is called the
least count of the screw gauge, that is,
Least count = pitch/N

3. Insert the given wire between the screw and the stud of the screw
gauge. Move the screw forward by rotating the rachet till the wire
is gently gripped between the screw and the stud as shown in Fig.
1.3. Stop rotating the rachet the moment you hear a click sound.

4. Take the readings on the linear scale and the circular scale.
5. From these two readings, obtain the diameter of the wire.
6. The wire may not have an exactly circular cross-section.

Therefore, it is necessary to measure the diameter of the wire for
two positions at right angles to each other. For this, first record
the reading of diameter d1 [Fig. 1.4 (a)] and then rotate the wire
through 90° at the same cross-sectional position. Record the
reading for diameter d2 in this position [Fig. 1.4 (b)].

Figure 3.4 Two magnified views (a) and (b) of a wire showing its
perpendicular diameters d1 and d2. d2 is obtained after the rotating
the wire in the clockwise direction through 90°

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 26

Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

7. The wire may not be truly cylindrical. Therefore, it is necessary to
measure the diameter at several different places and obtain the
average value of diameter. For this repeat the steps (3) to (6) for
three more positions of the wire.

8. Take the mean of the different values of diameter so obtained.

OBSERVATIONS

Micrometre/ Screw Gauge The length of the smallest division on the linear scale
= …………....... mm

Distance moved by the screw when it is rotated through x complete
rotations,

y =……………... mm
Pitch of the screw gauge

=y/x=…………….mm
Number of divisions on the circular scale,

n = .......................
Least Count (L.C.) of screw gauge

=pitch/No. of divisions on the circular scale
=……………..….mm

OBSERVATION TABLE

Reading along one direction Reading along perpendicular
(d1) direction
(d2)

S. Measured
No. Linear Circular Diameter Linear Circular Diameter diameter
Scale Scale d1 Scale Scale d2 D=[d1+d2]/2

reading, reading, =M+nxLC reading, reading, =M+nxLC

M (mm) n (mm) M (mm) n (mm)

1D=
1

2D=
2

3D=
3

4D=
4

CALCULATIONS
Mean measured diameter = [1D+2D+3D+4D]/4

=

=……….….mm

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 27

Micrometre/ Screw Gauge Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

PRECAUTIONS
1. Rachet arrangement in screw gauge must be utilised to avoid
undue pressure on the wire as this may change the diameter.
2. Move the screw in one direction else the screw may develop
“play”.
3. Screw should move freely without friction.
4. Reading should be taken at least at four different points along the
length of the wire.
5. View all the reading keeping the eye perpendicular to the scale to
avoid error due to parallax.

Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 28

Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

REVIEW QUESTIONS

Questions for Viva-Voce Q1. What is the principle of micrometer?
Q2. How accurate is a micrometer?
Q3. What is a micrometer made of?
Q4. What is micrometer used for?
Q5. What are the parts of Screw gauge?
Q6. How do you measure the pitch of a screw gauge?
Q7. What is zero error on a micrometer?
Q8. What is the range of a micrometer?
Q9. What size is a micrometer?
Q10. Draw free hand neat sketch of micrometer.

WRITE YOUR ANSWERS HERE

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Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 29

Questions for Viva-Voce Lakshmi Narain College of Technology (LNCT) Bhopal (MP)

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Mechanical Engineering Department | Lab Manual | Basic Mechanical Engineering [BT-203] 30