Physics for IGCSE & O level - Thermal Effects (Section 1)
1
Which type of surface is the best at reflecting thermal radiation and therefore appears cooler?
Răspuns
(C)
Shiny
2
Which state of matter has a fixed shape?
Răspuns
(A)
Solid
3
Which state of matter contains particles with the most kinetic energy?
Răspuns
(C)
Gas
4
Which type of wave does the sun emit that we can feel as heat?
Răspuns
(B)
Infrared waves
5
What causes the cooling effect experienced during evaporation?
Răspuns
(A)
The faster particles escape from the liquid.
6
What happens to the volume of a gas when heated at a constant pressure?
Răspuns
(A)
The volume increases.
7
What is a result of the convection of a hot water system?
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(C)
Cool water sinks and warm water rises
8
What happens to the particles of a solid when it is heated?
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(C)
They vibrate faster
9
What happens to the temperature during a change of state?
Răspuns
(C)
The temperature remains constant
10
What is the term used to describe the change in state from a liquid to a gas?
Răspuns
(C)
Vaporization
11
Why does a solid have a definite shape and volume?
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(D)
All of the above.
12
What happens to most substances when they are heated?
Răspuns
(B)
They expand
13
What happens to the latent heat during melting?
Răspuns
(B)
It is absorbed
14
What type of insulation is most commonly used to reduce heat loss from a house?
Răspuns
(D)
All of the above
15
During the convection in a liquid, water rises upwards as a:
Răspuns
(D)
hotter water
16
How does increasing the temperature of a gas affect the pressure, assuming the volume is constant?
Răspuns
(B)
The pressure increases.
17
What is the name of the unit that measures the temperature?
Răspuns
(C)
Celsius
18
Which color is a poor absorber of thermal radiation?
Răspuns
(B)
White
19
What does the term 'absolute zero' represent?
Răspuns
(C)
The temperature at which molecular motion stops.
20
Which statement is correct concerning the kinetic theory of matter?
Răspuns
(C)
Particles in a gas move randomly and have little to no attraction to each other.
21
What is the effect of high specific heat capacity?
Răspuns
(A)
Materials heat up and cool down slowly
22
What happens to the rate of evaporation if you increase the surface area?
Răspuns
(B)
It increases
23
What is the process of heat transfer called that occurs in direct contact?
Răspuns
(A)
Conduction
24
What does a thermocouple thermometer measure?
Răspuns
(B)
The force generated between two dissimilar metals due to a temperature difference
25
Which is the formula for calculating energy transfer?
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(B)
Energy Transferred = mass * specific heat capacity * temperature change
26
What is the main difference between a solid, liquid, and gas in terms of particle arrangement and movement?
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(C)
Solids have a fixed arrangement with limited movement, liquids have a less ordered arrangement with more movement, and gases have a very random arrangement with fast movement.
27
Which factor is responsible for increasing the rate of evaporation?
Răspuns
A
C
28
Which statement is correct about the specific latent heat of fusion?
Răspuns
(B)
Energy is absorbed when a substance melts.
29
In a convection current, why does the warmer fluid rise?
Răspuns
(A)
It is less dense.
30
How does the presence of clouds affect the Earth's temperature?
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(B)
They decrease the temperature by reflecting radiation
31
Why does a gas exert pressure on the walls of its container?
Răspuns
(C)
Because the gas molecules are colliding with the walls.
32
Which method of heat transfer is most significant in the oceans, transferring heat from the equator towards the poles?
Răspuns
(B)
Convection
33
Which of the following is a good thermal conductor?
Răspuns
(C)
Metal
34
In the context of evaporation, which of the following factors reduces the rate of evaporation?
Răspuns
(C)
Increasing the humidity
35
Which of the following explains why solids have a definite shape and volume?
Răspuns
(A)
Particles are tightly packed and held together by strong forces
36
What does convection require to occur?
Răspuns
(C)
A fluid
37
Which of the following is the correct unit for measuring the rate of heat transfer?
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(B)
Watt (W)
38
What type of surface is a poor reflector of thermal radiation?
Răspuns
(A)
Black
39
What happens to the volume of a gas if its temperature decreases while keeping pressure constant?
Răspuns
(B)
The volume decreases.
40
How does the specific heat capacity of a substance relate to its ability to store thermal energy?
Răspuns
(A)
Directly proportional: higher heat capacity, more energy stored.
41
What is the name for the heat required to change the state of a substance from liquid to gas?
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(C)
Latent heat of vaporization
42
Which term is defined as the total internal energy of a substance?
Răspuns
(C)
Internal energy
43
What is temperature?
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(B)
The average kinetic energy of the particles in a substance.
44
What is the transfer of energy by electromagnetic waves called?
Răspuns
(C)
Radiation
45
What does latent heat cause during a state change?
Răspuns
(C)
Temperature to remain constant.
46
What is the main reason for using insulating materials in the construction of buildings?
Răspuns
(B)
To reduce heat transfer
47
What is the role of thermal radiation on the Earth?
Răspuns
(A)
Heating up the Earth
48
Which of these materials is typically used in a bimetallic strip?
Răspuns
(A)
Two different types of metal.
49
What is Brownian motion?
Răspuns
(D)
The random movement of particles suspended in a fluid.
50
What is the name of the phenomenon describing the random movement of particles?
