4.2 Specific Heat Capacity

MODUL PDP SPM
PASCA PKP
NEGERI PERAK
2020

PHYSICS Form 4

4.2: 0
Specific
Heat
Capacity

4.2 Specific Heat Capacity

Learning Standard:

Pupils are able to:

• explain heat capacity, C.

• define specific heat capacity of a material, c.

=
(∆ )

• experiment to determine:

(i) the specific heat capacity of water

(ii) the specific heat capacity of aluminium

• communicate to explain the applications of specific heat capacity in daily life,

material engineering and natural phenomena.

• solve problems involving specific heat capacity using formula:

Q = mc∆θ

1

notE

Specific Heat Capacity

1. Diagram 1 shows two boys who are at the beach at noon. The boy who is walking on
the sand finds that the sand is very hot while the boy who is in the sea finds that the
sea water is very cold.

Concept: Heat capacity The sun heats up
the sand and sea

water at the
same period of

time

Sea water: high heat capacity
Sea water gets hot slowly

Sand : low heat capacity
Sand gets hot quickly

Diagram 1: Difference in temperature of sand and sea water at the beach

2. Heat capacity, C:
The quantity of heat needed to raise the temperature of the object by 1℃

= = heat capacity
∆ = quantity of heat supplied
Unit for C = ℃−1 ∆ = change in temperature

2

3.

Object X Rise in temperature, Object Y Rise in temperature,
∆ = 1℃ ∆ = 2℃

Heat, Q = 100 J Heat, Q = 100 J

Heat capacity, = Heat capacity, =
∆ ∆

= 100 = 100
1℃ 2℃

= 100 ℃−1 = 50 ℃−1

Heat capacity, > , rise in temperature of X < Y

4. Air Identical
= 1 kg cup

Air = 0.5 kg

Heat, Q = 100 J Heat, Q = 100 J

Time to boil, = 20 minutes Time to boil, = 10 minutes

Masa > , muatan haba >

5. Daily situations involving heat capacity:
(i) The soup in a large bowl is hotter compared to the same soup in a small bowl
that is left to cool for some time.

Soup in the Soup in the
big bowl is small bowl is

hotter less hot

3

(ii) Heat capacity of the dashboard of a car < heat capacity of the cushion fabric

Dashboard
Rise in temperature of

dashboard is higher
than the cushion fabric

Cushion fabric
(iii) Difference in temperature between cement court and grass at noon.

Temperature of cement court > grass

6. Specific heat capacity, c:

The quantity of heat needed to raise the temperature of 1 kg mass of the
substance by ℃.

= = specific heat capacity
∆ = quantity of heat supplied (J)

m = mass (kg)
∆ = change of temperature (℃/ K)

Unit for specific heat capacity, c = −1 ℃−1 atau −1 −1

7. = ∆
Q = quantity of heat absorbed/ released by the substance

4

8. The specific heat capacity of the metal aluminium, c = 900 −1 ℃−1 means:
1 kg of aluminium requires 900 J of heat to raise its temperature by 1 ℃.

9. Every substance has its own value of specific heat capacity as shown in Table 1.

Good cooling Table 1: Specific heat capacity of different substances
agent, high
value of c, Metal has
absorb large lower value
amount of
heat, small of c
compared to
rise in non-metal,
temperature metal gets
hot quickly

when
supplied with

the same
amount of

heat.

10. Application of specific heat capacity, c in daily life

(i) Selection of building materials of traditional houses in various climate zones
 Warm climate region

o Traditional houses which are built from wood (high specific heat
capacity) gets hot slowly.

o Wood = insulator of heat from the scorching sun.

5

 Region of cold climate

o Traditional houses are built from wood (high specific heat
capacity).

o Wood = good heat insulator because heat from fires lit in the
wooden houses cannot flow out.

(ii) Cooking utensils
 Metal wok

o Made of metal with low specific heat capaity, c, wok gets hot
quickly.

o Food can be fried at high temperature in a short time.
 Clay pot

o Made of clay, high specific heat capacity, c.
o Food can stay hot for a long time.

6

 Body & handle of a pot

o Body of the pot = aluminium (low specific heat capacity, c),
heats up quickly.

o Handle of the pot = plastic (high specific heat capacity, c), gets
hot slowly, safe to handle.

(iii) Car radiator system

Release heat in the hot water to avoid
overheating of the car engine.

Hot water flows
to the radiator.

Cold air is Water is
sucked in by pumped into the
fans so that heat engine block to
in the hot water absorb the heat
can be released
produced.
quickly.
Cooling agent = water (high specific heat capacity, c), able to
absorb heat produced from the burning of fuel in car engines.

(iv) Outer layer of space capsule

 Outer layer of space capsule is made from substance with a high
specific heat capacity, c and high melting point.

 Its journey back to Earth encounters air resistance when entering the
atmosphere and the high friction causes the space capsule to burn.

7

(v) Production of latest materials in the construction of green buildings, The
Diamond Building, Energy Commission

 The roof of Diamond Building is built with an insulating concrete roof
by using styrofoam boards.

 Styrofoam has high specific heat capacity, can reduce the absorption of
heat from the surroundings to reduce the temperature inside the
building.

(vi) Sea breeze Cold air from the
sea moves
The air on land
becomes hot and towards the land.

rises upwards

Lower specific Sea breeze
heat capacity, gets

hot quickly,
temperature rises

more quickly
during daytime.

(vii) Land breeze

Cold air above Hot air above the sea
the land moves rises upwards.
towards the sea.
High specific heat
Land breeze capacity,
occurs.
temperature in the
sea drops more
slowly than

temperature on land

8

11. Example of problem solving:

(i) A 0.5 kg metal block is heated by a 50 W electric heater for 90 s. The
temperature of the block rises from 20 ℃ to 45 ℃. Calculate the specific heat

capacity of the metal.

, = 0.5
ℎ , = 50
, = 90
, ∆ = 45 ℃ − 20 ℃ = 25 ℃
ℎ ℎ , = ?

=

= ∆
∆
(50)(90)
= (0.5)(25)

= 360 −1 ℃−1

9

4.2 MIND MAP

10

4.2 FAQ

No Question And Answer
1Q Is heat capacity the same as specific heat?

A Heat capacity is the quantity of heat needed to raise the temperature of
object by 1oC. Specific heat capacity is the quantity of heat needed to raise
2Q the temperature of 1 kg mass of substance by 1oC.
A
Why is specific heat capacity important?
3Q
A Specific heat capacity is a measure of the amount of heat energy required
to change the temperature of 1 kg of a material by 1oC. Hence it is
4Q important as it will give an indication of how much energy will be required
A to heat or cool an object of a given mass by a given amount.

5Q Why do different materials have different specific heat capacity?
A
Specific heat capacity depends upon the nature of the substance. If equal
6Q heat is provided to both the samples, because of difference in the number
A of molecules, the average kinetic energy will become more for the one
which has less number of molecules.

Why metals have low specific heat capacity?

Metal atoms in pure metal are very close together and are able to transfer
heat easily via conduction from one atom exciting the other atoms next to
it. So, the amount of energy it takes to heat a metal is relatively small to that
of water for example.

What are the applications of specific heat capacity?

Substances having a small specific heat capacity, are very useful as material
in cooking instruments such as frying pans, pots, kettles and so on, because,
they can be quickly heated up even when small amount of heat is
supplied.

How is specific heat capacity used in industry?

Substances that have a high specific heat capacity is suitable as a material
for constructing kettle handlers, insulators and oven covers, because, a high
amount of heat will cause only a small change in temperature. Therefore,
the material won't get hot too fast!

11

4.2 Exercise

SECTION A

1. The specific heat capacity of metal Q is 650 J kg-1 °C-1. The statement means that
A 650 J of heat is required to melt 1 kg of metal Q
B 650 J of heat is required to increase the temperature of metal Q by 1°C
C 650 J of heat is required to increase 1 g of metal Q form 0°C to 100°C
D 650 J of heat is required to increase the temperature of 1 kg of metal Q
by 1°C
[Mengetahui]

2 Water is suitable to be used as a cooling agent because of its
A high density
B high latent heat
C high specific heat capacity
D high adhesive force between the molecules
[Mengetahui]

3 A 1200 W kettle is filled with 0.5 kg of water at 28 °C. lt is turned on until the

water boils. What is the time taken to boil the water?
[Specific heat capacity of water = 4200 J kg-1 °C-1]

A 72 s
B 86 s
C 126 s
D 216 s

[Mengaplikasi Kuantitatif]

4 The Diagram below shows a frying pan. The body, base and handle of the frying
pan are made of different materials.

The following are materials P, Q, R and their respective specific heat capacities.
P 350 Jkg-1ºC-1
Q 890 Jkg-1ºC-1
R 2200 Jkg-1ºC-1

12

Which of the materials are suitable to be use as the body, base and handle of the
frying pan?

Base Body Handle
AQ R P
BR Q P
CP R Q
DP Q R

[Menganalisis]

5. A 0.5 kg metal block is heated by a 50 W electric heater for 90 s. Th e temperature of
the block rises from 20°C to 45°C. Calculate the specific heat capacity of the metal.
A 100 J kg-1 °C-1
B 225 J kg-1 °C-1
C 360 J kg-1 °C-1
D 450 J kg-1 °C-1
[Mengaplikasi Kuantitatif]

SECTION B

1. Diagram 1 show an aluminium block with mass 1kg and the temperature 27⁰C was
being heated using immersion heater of power 400 W.

Thermometer
Termometer

Aluminium block
Bongkah Aluminium

Power supply Felt cloth
Bekalan kuasa Kain felt

Hole
Lubang

Immersion heater Oil
Pemanas rendam Minyak

Polystyrene plate
Kepingan polisterin

Diagram 1

The temperature of the aluminium block was rise to 57oC after 4 minute.

13

a) What is the meaning of specific heat capacity?

[MENGETAHUI]

…………………………………………………………………………………………………………………………
(1 mark)

b) If the oil was replaced with water inside the aluminium block,

i) Estimate what will happen to time for the aluminium block to gain 57oC?

[Memahami]

…………………………………………………………………………………………………………………………
(1 mark)

ii) Give a reason for the answer in 1.b.(i)

[Memahami]

…………………………………………………………………………………………………………………………
(1 mark)

c) Calculate the specific heat capacity of the aluminium block.
(MENGAPLIKASI KUANTITATIF)

(2 marks)
d) Calculate the time needed to rise the temperature of the aluminium block to

47oC.
(MENGAPLIKASI KUANTITATIF)

(2 marks)

14

2 Diagram 2 shows two models of kettle.

Model A Model B

High density material Low density
material
High spesific heat
capasity Low spesific
heat capasity
Iron handle
Plastic handle

Diagram 2

a) What is the meaning of specific heat capacity?

[MENGETAHUI]

…………………………………………………………………………………………………………………………
(1 mark)

b) Based on the information in the diagram above, state the suitable
characteristics of the kettle to boil the water. Give your reason for each
characteristics

[MENGANALISIS]

i. Density

Reason

[2 marks]

ii. Specific heat capacity

Reason

[2 marks]
15

iii. Handle of kettle

Reason

[2 marks]

c) A kettle contains 4 kg of water. The average heat absorbed by the water is
200 Js−1 in 10 minutes. Calculate
(MENGAPLIKASI KUANTITATIF)

i. The amount of heat absorbed by the water

[1 mark]

ii. The rise in temperature of the water
[Specific heat capacity of water = 4200 J kg−1°C−1]

[1 mark]

d) Metals like iron and aluminium and always being used to make kettle, pan and

pot. Why metal is chosen to make kettle and pan? (MEMAHAMI)

[1 mark]

16

QR CODE

Title 4.2 Specific Heat Capacity QR CODE
link
4.2 SPECIFIC
HEAT CAPACITY https://youtu.be/6pnZTlwJBpY

4.2 SPECIFIC HEAT https://youtu.be/Es8TXSOl9Tw
CAPACITY PART 1

4.2 SPECIFIC HEAT https://youtu.be/RW8iRsMikTw
CAPACITY PART 2

Specific Heat https://youtu.be/YwRfg7JHJMk
Capacity
Experiment

REINFORCEMENT https://drive.google.com/file/d/15DHHxRcnsFdDR
TEST RpldrGHwlcWH_brIEQB/view?usp=sharing

ANSWER https://drive.google.com/file/d/1dkAL0CXHYKk1Ky
REINFORCEMENT N26d7oMmdvUMPEOocA/view?usp=sharing
TEST

17

4.2 ANSWER

SECTION A

1B
2C
3C
4D
5C

SECTION B Scheme Mark Total
No The quantity of heat required to increase the
1. a. temperature of 1 kg of substance by 1oC. 1 1
1 1
b.i More, more than 4 minute 1 1
b.ii
Water has greater heat capacity compare to oil

c. Q= mcӨ 1
Pt=mcӨ 12
400 x 4 x 60 = 1 x c x 30
96000 = 30c 1
c = 3200 J kg-1 oC-1 12

d. Q= mcӨ 7
Pt= mcӨ
400 x t = 1 x 3200 x 20
400t = 64000
t = 160 s

Total

2 a) Specific heat capacity of a substance is the amount of heat energy needed to
b) increase the temperature by 1oC for a mass of 1kg substance.
i. low density

light weight
ii. low specific heat capacity

water will boil faster
iii. plastic handle

low specific heat capacity /not easily be heated

18

c)(i) Q = Pt
Q = 200×10× 60
Q = 120000J

(ii) Q = mcθ
120000 = 4kg × 4200×θ
θ = 7.14 0C

d) Iron and Aluminium have smaller specific heat capacity and heated up faster.Thus,
the food can be cooked faster.

19