DP014 : TUTORIAL FLIPBOOK 2/2

PHYSICS UNIT KMNS

PHYSICS
TUTORIAL
BOOKLET

DP014

2021/2022

Flipbook 2/2
(Topic 5-8)

PHYSICS UNIT PHYSICS UNIT

COPY RIGHT PHYSICS UNIT KMNS

CONTENTS i
ii
THE GREEK ALPHABET iv
LIST OF SELECTED CONSTANT VALUES
LIST OF SELECTED FORMULAE 1
TOPIC 1: INTRODUCTION TO PHYSICS 7
TOPIC 2: KINEMATICS OF LINEAR MOTION 14
TOPIC 3: MOMENTUM AND IMPULSE 20
TOPIC 4: FORCES 26
TOPIC 5: WORK AND ENERGY 32
TOPIC 6: CIRCULAR MOTION 37
TOPIC 7: ROTATIONAL OF RIGID BODY 43
TOPIC 8: HEAT, GAS LAW AND THERMODYNAMICS

THE GREEK ALPHABET

A  Alpha

B  Beta

 Gamma

  Delta

  Epsilon

  Zeta

  Eta

 Theta

  Iota

  Kappa

  Lambda

 Mu

 Nu.

  Xi

  Omicron

 Pi

  Rho

  Sigma

  Tau

  Upsilon

  ,  Phi

  Chi

  Psi

  Omega

i

LIST OF SELECTED CONSTANT VALUES
SENARAI NILAI PEMALAR TERPILIH

ii

LIST OF SELECTED CONSTANT VALUES
SENARAI NILAI PEMALAR TERPILIH

iii

LIST OF SELECTED FORMULAE
SENARAI RUMUS TERPILIH

iv

Physics Unit, KMNS DP014

TOPIC 5
WORK AND ENERGY
5.1 Work
a) Define work done by a constant force.
b) Explain the physical meaning of the dot product, = ∙ .
c) Use the equation for work done by a constant force, =
d) Determine work done from F-s graph.

5.2 Energy and Conservation of Energy

a) Define:

i) kinetic energy.

ii) gravitational potential energy.

iii) elastic potential energy.

b) Use:

i) kinetic energy, = 1 2

2

ii) gravitational potential energy, = ℎ

iii) elastic potential energy, = 1 2
2

c) State the principle of conservation of energy.

d) Apply the principle of conservation of energy.

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Physics Unit, KMNS DP014

OBJECTIVE QUESTIONS
(C2, PLO 1, MQF LOD 1)

1. Below is the definition of work done, EXCEPT
A. Scalar (dot) product between force and displacement of a body.
B. Product of the component of the force perpendicular to the displacement
times the displacement of a body.
C. Work done by a force of 1 N which results in a displacement of 1 m in the
direction of the force, is equals to 1 Joule (J).
D. Product of the magnitude of the component of the force parallel to the
displacement times the magnitude of displacement of a body.

2. What is the SI unit for work done?
A. Watt (W).
B. Joule (J).
C. Second (s).
D. Joule per second (J s-1).

3. Work done can be represented by the area under the graph of
A. force - time.
B. force - distance.
C. force - velocity.
D. force – displacement.

4. Principle of conservation of energy states that
A. in an isolated (closed) system, the total energy of that system is zero.
B. in an isolated (closed) system, the total energy of that system is constant.
C. in an isolated (closed) system, the total potential energy of that system is
constant.
D. in an isolated (closed) system, the total kinetic energy of that system is
constant.

5. The total energy possessed by a moving body
A. varies from point to point.
B. is constant at every instant.
C. is maximum in the start and minimum at the end.
D. is minimum in the start and maximum at the end.

ANSWERS:
1. B 2. B 3. D 4. B 5. B

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Physics Unit, KMNS DP014
STRUCTURED QUESTIONS (C3, PLO 3, CTPS 2, MQF LOD 6)
F = 30 N
1.

600 s = 0.8 m
A

FIGURE 5.1

Calculate the work done by force, F on an object A as shown in FIGURE 5.1.

2. A boy pushes a box with a constant force of 180 N at an angle of 30° with the
horizontal. How much work is done if the box is pushed through a distance of
15.0 m?

3. A 3.0 kg box is lifted vertically from rest to a distance of 2.0 m with a constant
upward applied force of 60.0 N. Calculate the.
(a) work done by the applied force.
(b) work done by gravity.
(c) work done by net force.

4.

F
370

FIGURE 5.2
FIGURE 5.2 shows a woman drags her luggage of mass 20.0 kg with a force,
F at a constant velocity across the floor as shown in FIGURE 5.2. The kinetics

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Physics Unit, KMNS DP014

friction, fk between the rollers of the luggage and the floor is 60 N. The luggage
is dragged 0.80 m along the floor. Calculate the
(a) work done on the luggage by the normal force.
(b) work done on the luggage by kinetics force, fk.
(c) work done on the luggage by force, F.
(d) total work done on luggage.

5.
F (N)

350 x (cm)
300
250
200
150
100
50

1 2 345 6 7

FIGURE 5.3
FIGURE 5.3 shows the graph of magnitude of force F exerted by a given spring
as a function of the distance the spring is stretched, x. Calculate the work done
when the spring is stretched from
(a) x = 0 cm to x = 5 cm.
(b) x = 2 cm to x = 7 cm.

6.
F (N)

15
10
5
0
-5 1 2 3 4 5 6 7 x (m)
-10
-15

FIGURE 5.4
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Physics Unit, KMNS DP014

(a) A body moves in a straight line under action of a force varying with
displacement as shown in FIGURE 5.4. Find the work done by the force.

(b) Is there any work done on the object from x = 0 m to x = 1 m? Explain.

7. A 200 g object is dropped from a height of 10 m from the ground. By using
principle of conservation of energy, determine the speed of the object just
before it hits the ground.

8.

6m

FIGURE 5.5
FIGURE 5.5 shows an object is released from the top of a 6.0 m smooth inclined
plane. By using principle of conservation of energy, determine the speed at the
end of the plane?

9. A force of magnitude 800 N caused an extension of 20.0 cm on a spring.
Determine the
(a) spring constant.
(b) elastic potential energy of the spring when the extension of the spring is
30.0 cm.

10.

3m DE

A B C
4.5 m FIGURE 5.6

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Physics Unit, KMNS DP014

FIGURE 5.6 shows a small cart of mass 3.5 kg moves on the frictionless track
AE with a speed of 15.0 ms-1 along AB, down to C and climbs up to D and E.
(a) Calculate the kinetic energy of the cart as it moves along AB.
(b) State the point where the cart’s kinetic energy is a maximum. Explain

your answer.
(c) Calculate the change in the potential energy of the cart between B and

D.
(d) Determine the kinetic energy of the cart as it moves along DE.
(e) Calculate the speed of the cart at point C.

ANSWERS:

1. 12 J

2. 2.34 x 103 J

3. (a) 120 J (b) -58.86 J (c) 61.14 J

4. (a) 0 J (b) -48 J (c) 48 J (d) 0 J

5. (a) 6.25 J (b) 11.25 J

6. (a) 22.5 J

7. 14.01 m s-1

8. 10.85 m s-1

9. (a) 4000 N m-1 (b) 180 J

10. (a) 393.75 J (c) 103.01 J (d) 290.75 J (e) 17.7 m s-1

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Physics Unit, KMNS DP014

TOPIC 6

CIRCULAR MOTION

6.1 Uniform circular motion
a) Describe uniform circular motion.
b) Convert units between degrees, radian and revolution or rotation.

6.2 Centripetal force
a) Define centripetal acceleration
b) Use centripetal acceleration ac=v2/r
c) Define centripetal force
d) Use centripetal force Fc=mv2/r
e) Solve problems related to centripetal force for uniform circular motion for
horizontal circular motion.

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Physics Unit, KMNS DP014

OBJECTIVE QUESTIONS

(C2, PLO 1, MQF LOD 1)

1. For an object to move in a uniform circular motion, it must move with

A. constant speed
B. constant velocity
C. constant momentum
D. constant linear acceleration

2. A body is moving in a circular motion. Which row in the table below correctly
describes the linear speed, velocity and linear acceleration of the body?

Linear speed Angular velocity Linear acceleration

A. Constant Constant Varying

B. Constant Constant Zero

C. Constant Varying Constant

D. Varying Constant Varying

3. Object moving along a circular path is
A. in equilibrium
B. not in equilibrium
C. not moving with constant speed
D. in random motion

4.

FIGURE 6.1

FIGURE 6.1 shows a particle moves with uniform speed, v in a circle of radius,r.
The period of the circular motion is T. What is the centripetal acceleration of the
particle when it moves from one end X of a diameter to the other end Y?

A. Zero B. v2 C. 2v D. v
r T 2T

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Physics Unit, KMNS DP014

5. A car moving on a horizontal road may be thrown out of the road is taking a
turn

A. by the gravitational force
B. due to the lack of proper centripetal force
C. due to the lack of frictional force between the tire and the road
D. due to the reaction of the ground

ANSWERS:
1. A 2. B 3. B 4. B 5. C

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Physics Unit, KMNS DP014

STRUCTURED QUESTIONS

(C3, PLO 4, CTPS 2, MQF LOD 6)

1. (a) How many radians is the angular displacement when there is a rotation
through
(i) a quarter of a revolution?
(ii) a two third of a revolution?

(b) What is the angular velocity of
(i) a flywheel rotating at 5000 revolutions per minute.
(ii) the minute-hand of a clock.
(iii) a point on the Equator of the Earth.

2. The frequency and angular velocity of a second-hand clock is?

3. A person is staying in a country situated at the equator. The radius of earth is
6400 km and is rotating 24 hours per revolution about its axis. Calculate
(a) the angular velocity of the earth’s rotation.

(b) the speed of the person as the earth rotates.

(c) Does the person realize that he is moving with the speed calculated in
(b)? Give your reason to support your answer.

4. An object is moving at a constant velocity on a horizontal circular path of radius
6 m. If the frequency of the object is 0.2 Hz, what is the centripetal acceleration
acting on the object?

5. A 55.0 kg ice skater is moving at 4.0 m/s when she grabs the loose end of a
rope, the opposite end of which is tied to a pole. She then moves in a circle of
radius 0.8 m around the pole. Determine the force exerted by the horizontal
rope on her arms

6. If an object of mass 3.5 kg is travelling in a circular path with a radius of 3.14 m
at a speed of 3.46 m s-1, what will be
(a) the centripetal acceleration on that object?
(b) the centripetal force on that object?

7. An 8.0 g cork is swung in a horizontal circle with a radius of 35 cm. It makes
30 revolutions in 12 seconds. What is the tension in the string?

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Physics Unit, KMNS DP014

8. A 2000 kg car rounds a circular turn of radius 20 m. If the road is flat and the
coefficient of friction between tires and road is 0.70, how fast can the car go
without skidding?

9. A 1200 kg car drives at a constant speed of 14 m/s around a circular track
(r = 80.0m).
(a) What is the magnitude of the net force acting on the car?

(b) If the coefficient of static friction is 0.3, how fast can the car move before
it start sliding?

10.

FIGURE 6.2

A 1500 kg car is moving on a flat, horizontal curved road as shown in
FIGURE 6.2. If the radius of the curve is 35 m and the coefficient of static friction
between the tires and dry road is 0.5,
(a) calculate the maximum speed of the car to successfully make a turn.

(b) suppose the car travels on this curve on a wet day and begins to skid
when its speed reaches 8 m s-1. Calculate the coefficient of static friction.

ANSWERS:

1. (a) π/2 rad, π/3 rad

(b) 523.6 rad s-1, 1.75 x 10-3 rad s-1, 7.27 x 10-5 rad s-1

2. 0.105 rad s−1

3. (a) 7.27×10-5 rad s-1 (b) 465.28 m s-1

4. 9.47 m s−2

5. 1100 N

6. (a) 3.81 m s -2 (b) 13.34 N

7. 0.691 N

8. 11.72 m s-1

9. (a) 2940 N (b) 15.34 m s-1

10. (a) 13.102 m s-1 (b) 0.186

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Physics Unit, KMNS DP014

TOPIC 7
ROTATIONAL OF RIGID BODY

7.1 Rotational kinematics

a) Define:
i. Angular displacement, θ
ii. Average angular velocity,
iii. Instantaneous angular velocity, ω
iv. Average angular acceleration,
v. Instantaneous angular acceleration, α.

b) Use:
i. Angular displacement, θ

ii. Average angular velocity,
iii. Instantaneous angular velocity, ω

iv. Average angular acceleration,
v. Instantaneous angular acceleration, α.

c) State parameters in rotational motion with their corresponding quantities
in linear motion.

d) Use parameters in rotational motion with their corresponding quantities in
linear motion:

=

=

=

= 2 = 2


e) Solve problems related to rotational motion with constant angular
acceleration.

ω = +

= + 1 2 and
2

2 = 2 + 2

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Physics Unit, KMNS DP014
OBJECTIVE QUESTIONS (C2, PLO 1, MQF LOD 1)

1. A rigid body is rotating about an axis passing through its centre. Every point on the
body has
A. different angular speed but same linear speed.

B. same angular speed and angular acceleration.

C. same angular speed but different angular acceleration.

D. different angular speed but same angular acceleration.

2. Which of the following is CORRECT?
A. Angular displacement is an angle through which a point or line has been
rotated in a specified direction about a specified axis

A. Average angular velocity is an instantaneous rate of change of angular
displacement.

B. Average angular acceleration is the rate of change of angular
displacement.

D. Instantaneous angular acceleration is an instantaneous rate of change
of angular displacement.

3. Which of the following is true about a rotating rigid body?
A. Its centre of rotation is at rest.

B. The centre of rotation is at the centre mass.

C. All position on the body is moving the same linear velocity.

D. All points in the body are moving with the same angular velocity.

4. Hasan sits on the outer rim of a merry-go-round, and Husin sits midway between
the center and the rim. The merry-go-round makes one revolution every two
seconds. Who has the longer linear (tangential) velocity?
A. Husin.

B. Hasan.

C. both the same.

D. linear velocity is zero for both of them.

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Physics Unit, KMNS DP014

5. A disc of 2 cm in radius rotates about its axis. Compare the angular speed of a
point near the center of the disc to a point on the rim of the disc.
A. >

B. <

C. =

D. 2 =

ANSWER:
1. B 2. A 3. D 4. B 5. C

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Physics Unit, KMNS DP014

STRUCTURED QUESTIONS

(C4, PLO 4, CTPS 3, MQF LOD 6)

1. An object at rest begins to rotate with a constant angular acceleration. If this
object rotates through an angle θ in the time t, through what angle did it rotates
in the time ½ t?

2. An object at rest begins to rotate with a constant angular acceleration. If this
object has angular velocity ω at time t, what was its angular velocity at the time
½ t?

3. A flywheel is accelerated uniformly from rest for 6.00 s. It is observed that at
the end of the 6.00 s, the flywheel rotates through an angle of 450 radians.
Calculate for the flywheel
(a) the average angular velocity during the 6.00 s.
(b) the angular velocity at the end of the 6.00 s.
(c) the angular acceleration.

4. A rigid body rotates about a fixed axis through a point in the body, with uniform
angular velocity of 600 r.p.m. The velocity then decreases at a constant
retardation to 300 r.p.m. in 6.0 s. Determine:
(a) the angular acceleration,
(b) the number of revolutions the body has turned through in the 6.0 s,
(c) the extra time needed by the body to come to a stop if it continues to
slow down at the same rate.

5. (a) A centrifuge accelerates uniformly from rest to 15,000 rpm in 220 s.
Through how many revolutions did it turn in this time?

(b) An automobile engine slows down from 4500 rpm to 1200 rpm in 2.5 s.
Calculate
(i) its angular acceleration, assumed constant, and
(ii) the total number of revolutions the engine makes in this time.

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Physics Unit, KMNS DP014

6. A cooling fan is turned off when it is running at 850 rev/min. It turns 1500
revolutions before it comes to a stop.
(a) What was the fan’s angular acceleration, assumed constant?

(b) How long did it take the fan to come to a complete stop?

7. A small rubber wheel is used to drive a large pottery wheel, and they are
mounted so that their circular edges touch. The small wheel has a radius of
2.0cm and accelerates at the rate of 7.2 rad/s2 and it is in contact with the
pottery wheel (radius 25.0 cm) without slipping. Calculate
(a) the angular acceleration of the pottery wheel, and
(b) the time it takes the pottery wheel to reach its required speed of 65 rpm,
if it is start from rest.

8. The tires of a car make 65 revolutions as the car reduces its speed uniformly
from 95 km/h to 45 km/h. The tires have a diameter of 0.80 m.
(a) What was the angular acceleration of the tires?
(b) If the car continues to decelerate at this rate, how much more time is
required for it to stop?

9. A disk 3.5 cm in diameter rotates with a period of 0.2 s. What is
(a) the angular speed of the disk and
(b) the linear speed of a point on the rim of the disk?
(c) Does a point near the center of the disk have an angular speed that is
greater than, less than, or the same as the angular speed found in part
(a)? Explain.

10. A compact disk (CD) speeds up uniformly from rest to 310 rpm in 3.0 s.
Calculate the number of revolutions the CD makes in this time.

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Physics Unit, KMNS DP014

ANSWER: (b) 150 rad s-1 (c) 25 rad s-2

1. ¼ θ (b) 45 rev (c) 6.0 s
2. ½ ω
3. (a) 75 rad s-1 (b) -1.38 x102 rad s-2, 118.75 rev
4. (a) - 5/3 π rad s-2
5. (a) 2.75 x 104 rev (b) 211.76 s
6. (a) - 0.42 rad s-2
7. (a) 0.576 rad s-2 (b) 11.82 s
8. (a) -4.13 rad s-2
9. (a) 31.42 rad s-1 (b) 7.57 s
10. 7.75 rev
(b) 54.95 cm s-1

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Physics Unit, KMNS DP014

TOPIC 8
HEAT, GAS LAW AND THERMODYNAMICS

8.1 Heat
a) Define heat conduction.
b) Solve problems related to rate of heat transfer, = − ( ) through a



cross-sectional area. *only one material
c) Discuss graphs of temperature-distance, T-x for heat conduction through

insulated. *one material & lagged material.

8.2 Ideal gas equations
a) State Gas’s Law
b) Sketch the following graphs of an ideal gas:
i. p-V graph at constant temperature.
ii. V-T graph at constant pressure.
iii. p-T graph at constant volume.
c) Explain the following graphs of an ideal gas:
i. p-V graph at constant temperature.
ii. V-T graph at constant pressure.
iii. p-T graph at constant volume.
d) State ideal gas equation
e) Use ideal gas equation, pV=nRT

8.3 Thermodynamics
a) State the first law of thermodynamics.
b) Solve problem related to first law of thermodynamics.
c) Define the thermodynamics processes
i. Isothermal
ii. Isochoric
iii. Isobaric
iv. Adiabatic
d) Interpret p-V graph for all the thermodynamics processes.
(Experiment 6: Heat)

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Physics Unit, KMNS DP014
OBJECTIVE QUESTIONS (C2, PLO 1, MQF LOD 1)

1. Which of the following statements best represents the characteristic of heat as a
form of energy?
A. Heat needs a medium
B. The magnitude of heat depends on its density
C. Heat is transferred from a point or region to another
D. Heat is transferred from a high pressure region to low pressure region

2. Thermal conductivity, k depends on

A. the type of material C. the triple point of the material

B. the shape of the material D. the boiling point of the material

3. State Boyle’s Law and Charles’s Law.

Boyle’s law Charles’s Law

A. The volume of a fixed mass of gas The pressure of a fixed mass of gas at

at constant pressure is directly constant temperature is inversely

proportional to its absolute proportional to its volume.

temperature

B. The pressure of a fixed mass of gas The pressure of a fixed mass of gas at

at constant temperature is inversely constant volume is directly proportional

proportional to its volume. to its absolute temperature

C. The pressure of a fixed mass of gas The volume of a fixed mass of gas at

at constant temperature is inversely constant pressure is directly

proportional to its volume. proportional to its absolute temperature

D. The pressure of a fixed mass of gas The volume of a fixed mass of gas at

at constant volume is directly constant pressure is directly

proportional to its absolute proportional to its absolute temperature

temperature

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Physics Unit, KMNS DP014

4. Based on the first law of thermodynamic, in which the equation is Q = ΔU +W,
which of the following statement is correct?

A. When a piston is being compressed, the work is done by the gas.

B. When the heat is out of the system, the value of Q is positive in sign.
C. The change in internal energy, ΔU is mainly dependent on temperature.

D. When an ideal gas expands and undergoes changing in volume, there is
no work done on the gas.

5. An ideal gas undergoes an isothermal process. Which of the following law can
be applied to the gas?
A. Boyle’s law
B. Charles’ law
C. Pascal’s law

D. Pressure law

ANSWER:
1. C 2. A 3. C 4. C 5. A

45

Physics Unit, KMNS DP014
STRUCTURED QUESTIONS (C3, PLO 4, CTPS 2, MQF LOD 6)

1. An aluminum rod has a diameter of 3.0 cm and thickness of 0.6 m. One end of
the rod is placed in boiling water and the other end in ice. Calculate the quantity
of heat transferred through the rod within 1 minute. Given, k = 205 W m-1 K-1.

2. The rate of heat conduction is 80 kJ per hour at a thin wall with an area of
14.0 cm2. If the temperature gradient across the wall is 15 0C m-1, calculate the
thermal conductivity of the wall.

3. A glass window of cross-sectional area 1.50 m2 and thickness 0.20 cm is closed
in winter. The temperatures of the inner and outer surfaces of the window are 15
°C and 0 °C.

(a) Calculate the rate of heat flow through the window.

(b) Suggest how you would reduce the amount of heat loss to the
surroundings through this window.
(Thermal conductivity of glass = 0.84 W m-1 K-1)

4. (a) Calculate the number of mole of CO2 contained in a 500 cm3 flask at a
pressure of 2.0 x 105 Pa and temperature of 100 0C.

(b) Calculate the volume of CO2 if the gas heated at constant pressure of 2.0
x 105 Pa to 120 0C.

5. 5 g of oxygen gas occupies 2.0 L at a pressure of 2.2 x 105 Pa. Calculate the
temperature of gas.

6. Calculate the pressure for 5 g of oxygen gas of volume of 500 cm3 at temperature
of 150oC. Assume that oxygen behaves likes an ideal gas.
(Molar mass of oxygen gas = 32 g mol-1)

7. In each of the following situations, find the change in internal energy of the
system.
(a) A system absorbs 2090 J of heat and at the same time does 400 J of work.
(b) A system absorbs 1255 J of heat and at the same time 420 J of work is
done on it.
(c) 5020 J is removed from a gas held at constant volume.

Give your answers in kilojoules.

46

Physics Unit, KMNS DP014

8. Sketch p-V graph for all the thermodynamic (isothermal, isochoric, isobaric and
adiabatic) processes in the same axes.

9. As an ideal gas is compressed isothermally, the compressing agent does 36 J of
work. How much heat flows from the gas during the compression process?

10. (a) A gas undergoes the following thermodynamic processes: isobaric
expansion, heated at constant volume, compressed isothermally and
finally expands adiabatically back to its initial pressure and volume. Sketch
all processed given on the same p-V graph.

(b) A gas of volume 0.02m3 at a pressure of 2.0 × 105 Pa undergoes an
isothermal compression. If the final pressure is 4.0×105 Pa, what is its
volume?

11. P(Pa)
B

C
A

V (m3)

FIGURE 8.1

A sample containing 1.00 mole of the ideal gas helium undergoes the cycle of
operations as shown in FIGURE 8.1 above. BC is an isothermal process.
Pressure at point A is stp and pressure at B is 2.0 atm. Calculate

(a) Temperature at A.

(b) Temperature at B.

(c) Volume at C

(stp: 1 atm = 1.013×105 Pa, T = 273.15 K, V = 0.0224 m3)

47

Physics Unit, KMNS DP014
ANSWER:

1. 1449.06 J (b) 5.27 x 10-4 m3
2. 1058.2 W m-1 K-1
3. (a) 9450 Js-1 (b) 1.68 kJ (c) –5.02 kJ

4. (a) 0.03225 mole (b) 0.01 m3

5. 338.87 K (b) 546.12 K (c) 4.48 x 10-2 m3
6. 1.10 x 106 Pa

7. (a) 1.69 kJ

8. Refer Notes
9. –36 J

10. (a) Refer Notes

11. (a) 273.06 K

48