1.
Heat is a form of: A) Matter
B) Energy
C) Force
D) Power
2.
The SI unit of heat is: A) Calorie
B) Erg
C) Joule
D) Watt
3.
The instrument used to measure temperature is: A) Barometer
B) Thermometer
C) Hygrometer
D) Calorimeter
4.
Temperature is a measure of: A) Heat content
B) Internal energy
C) Average kinetic energy of molecules
D) Potential energy
5.
One calorie is equal to: A) 2.18 J
B) 3.18 J
C) 4.18 J
D) 5.18 J
6.
Heat flows from: A) Cold body to hot body
B) Hot body to cold body
C) Low mass to high mass
D) High density to low density
7.
The SI unit of specific heat capacity is: A) J/kg
B) J/kg°C
C) J/m³
D) W/mK
8.
The amount of heat required to raise the temperature of 1 kg of a substance by 1°C is called: A) Heat capacity
B) Thermal conductivity
C) Specific heat capacity
D) Latent heat
9.
Water has: A) Low specific heat
B) High specific heat
C) Zero specific heat
D) Infinite specific heat
10.
The specific heat of water is approximately: A) 4200 J/kg°C
B) 2100 J/kg°C
C) 8400 J/kg°C
D) 1050 J/kg°C
11.
A device used to measure heat exchanged is: A) Thermometer
B) Calorimeter
C) Barometer
D) Hydrometer
12.
The principle of calorimetry is based on: A) Conservation of momentum
B) Conservation of mass
C) Conservation of energy
D) Boyle’s law
13.
The quantity of heat required to change a solid into liquid without temperature change is: A) Specific heat
B) Heat capacity
C) Latent heat of fusion
D) Latent heat of vaporization
14.
The SI unit of latent heat is: A) J/kg
B) J
C) W
D) N
15.
The melting point of ice is: A) 0°C
B) 32°C
C) 100°C
D) -32°C
16.
The boiling point of water at standard pressure is: A) 50°C
B) 80°C
C) 100°C
D) 120°C
17.
The transfer of heat through direct contact is: A) Radiation
B) Conduction
C) Convection
D) Reflection
18.
Conduction mainly occurs in: A) Solids
B) Liquids
C) Gases
D) Vacuum
19.
The transfer of heat through the movement of particles is: A) Conduction
B) Radiation
C) Convection
D) Reflection
20.
Convection occurs mainly in: A) Solids
B) Liquids and gases
C) Vacuum
D) Metals only
21.
Heat transfer without a material medium is: A) Conduction
B) Convection
C) Radiation
D) Evaporation
22.
Solar energy reaches Earth by: A) Conduction
B) Convection
C) Radiation
D) Diffusion
23.
Good conductors of heat are generally: A) Plastics
B) Rubber
C) Metals
D) Wood
24.
A poor conductor of heat is: A) Copper
B) Aluminum
C) Iron
D) Wood
25.
The rate of heat flow depends on: A) Temperature difference
B) Area
C) Thickness
D) All of these
26.
The unit of thermal conductivity is: A) W/mK
B) J/kg
C) N/m²
D) kg/m³
27.
Copper is used in cooking utensils because it: A) Is cheap
B) Is light
C) Conducts heat well
D) Is magnetic
28.
Woolen clothes keep us warm because: A) They generate heat
B) They absorb heat
C) Air trapped in them is a poor conductor
D) They reflect light
29.
Land breeze occurs: A) Daytime
B) Nighttime
C) Morning only
D) Evening only
30.
Sea breeze occurs: A) Nighttime
B) Daytime
C) Winter only
D) Summer night
31.
The process of changing liquid into vapor at all temperatures is: A) Boiling
B) Condensation
C) Evaporation
D) Sublimation
32.
Evaporation causes: A) Heating
B) Cooling
C) Melting
D) Freezing
33.
The latent heat of vaporization of water is approximately: A) 2.26 × 10⁶ J/kg
B) 3.26 × 10⁶ J/kg
C) 1.26 × 10⁶ J/kg
D) 4.26 × 10⁶ J/kg
34.
The process in which vapor changes into liquid is: A) Evaporation
B) Condensation
C) Melting
D) Sublimation
35.
The direct conversion of solid into gas is: A) Melting
B) Condensation
C) Sublimation
D) Freezing
36.
Dry ice is: A) Frozen water
B) Solid oxygen
C) Solid carbon dioxide
D) Solid nitrogen
37.
The lower fixed point on Celsius scale is: A) Boiling point of water
B) Freezing point of water
C) Room temperature
D) Absolute zero
38.
The upper fixed point on Celsius scale is: A) 50°C
B) 80°C
C) 100°C
D) 120°C
39.
Absolute zero temperature is: A) -273°C
B) -173°C
C) -373°C
D) 0°C
40.
The SI unit of temperature is: A) Celsius
B) Fahrenheit
C) Kelvin
D) Rankine
41.
0°C corresponds to: A) 273 K
B) 100 K
C) 373 K
D) 0 K
42.
The Kelvin scale has: A) Negative temperatures
B) No negative temperatures
C) Only positive temperatures above 100
D) Only integers
43.
The relation between Celsius and Kelvin is: A) K = °C + 273
B) K = °C – 273
C) K = °C × 273
D) K = °C ÷ 273
44.
The normal human body temperature is: A) 35°C
B) 37°C
C) 40°C
D) 42°C
45.
Which thermometer is used for measuring body temperature? A) Laboratory thermometer
B) Clinical thermometer
C) Gas thermometer
D) Resistance thermometer
46.
The range of a clinical thermometer is: A) 0–100°C
B) 35–42°C
C) -10–110°C
D) 20–80°C
47.
The expansion of solids due to heating is called: A) Thermal expansion
B) Compression
C) Contraction
D) Refraction
48.
On heating, most substances: A) Expand
B) Contract
C) Remain unchanged
D) Melt instantly
49.
The SI unit of coefficient of linear expansion is: A) °C
B) m
C) °C⁻¹
D) J
50.
Railway tracks are provided with gaps to allow: A) Cooling
B) Expansion
C) Lubrication
D) Cleaning
51.
Thermostats work on: A) Thermal expansion
B) Reflection
C) Refraction
D) Magnetism
52.
A bimetallic strip consists of: A) Two metals
B) Two liquids
C) Two gases
D) Two plastics
53.
The expansion of liquids is generally: A) Less than solids
B) More than solids
C) Zero
D) Negative
54.
The expansion of gases is: A) Least
B) Moderate
C) Greatest
D) Zero
55.
The anomalous expansion of water occurs between: A) 0°C and 4°C
B) 4°C and 8°C
C) 10°C and 20°C
D) 20°C and 30°C
56.
Water has maximum density at: A) 0°C
B) 2°C
C) 4°C
D) 10°C
57.
Ice floats on water because: A) Ice is heavier
B) Ice is denser
C) Ice is less dense than water
D) Water expands downward
58.
Black surfaces are: A) Good absorbers
B) Poor absorbers
C) Good reflectors
D) Transparent
59.
Shiny surfaces are: A) Good absorbers
B) Poor reflectors
C) Good reflectors
D) Good emitters only
60.
A thermos flask minimizes heat transfer by: A) Conduction only
B) Convection only
C) Radiation only
D) All three modes
61.
The vacuum in a thermos flask prevents: A) Radiation
B) Conduction and convection
C) Reflection
D) Expansion
62.
The silvered walls of a thermos flask reduce: A) Conduction
B) Convection
C) Radiation
D) Evaporation
63.
The heat capacity of a body depends on: A) Mass
B) Material
C) Both A and B
D) Temperature only
64.
Heat capacity is measured in: A) J/°C
B) J/kg°C
C) W/mK
D) kg/J
65.
Specific heat is highest for: A) Copper
B) Iron
C) Water
D) Silver
66.
The formula for heat gained or lost is: A) Q = mcΔT
B) F = ma
C) V = IR
D) P = VI
67.
In Q = mcΔT, c represents: A) Mass
B) Temperature
C) Specific heat capacity
D) Heat
68.
When ice melts: A) Temperature rises
B) Temperature falls
C) Temperature remains constant
D) Pressure becomes zero
69.
Boiling occurs: A) At the surface only
B) Throughout the liquid
C) In solids only
D) In gases only
70.
Evaporation occurs: A) Throughout liquid
B) At the surface only
C) In solids only
D) In vacuum only
71.
The SI unit of thermal conductivity includes: A) Watt
B) Meter
C) Kelvin
D) All of these
72.
The transfer of heat in a vacuum is: A) Impossible
B) By radiation only
C) By conduction only
D) By convection only
73.
Hot air rises because: A) It becomes denser
B) It becomes lighter
C) Gravity decreases
D) Pressure vanishes
74.
The cooling effect of perspiration is due to: A) Condensation
B) Evaporation
C) Conduction
D) Radiation
75.
Heat is measured using: A) Calorimeter
B) Ammeter
C) Voltmeter
D) Galvanometer
76.
The boiling point of water decreases when: A) Pressure increases
B) Pressure decreases
C) Density increases
D) Humidity increases
77.
Pressure cookers cook food faster because: A) Pressure lowers boiling point
B) Pressure raises boiling point
C) Less heat is used
D) Water evaporates faster
78.
The energy emitted by a hot body is: A) Thermal radiation
B) Convection current
C) Latent heat
D) Expansion energy
79.
The color that absorbs maximum radiant heat is: A) White
B) Yellow
C) Black
D) Silver
80.
White clothes are preferred in summer because they: A) Absorb heat
B) Reflect heat
C) Produce cooling
D) Conduct heat
81.
The unit of heat capacity is: A) J/K
B) J/kg
C) W/K
D) kg/K
82.
Which has the highest thermal conductivity? A) Wood
B) Glass
C) Copper
D) Air
83.
The process opposite to sublimation is: A) Deposition
B) Melting
C) Boiling
D) Evaporation
84.
The coefficient of volume expansion is measured in: A) m³
B) °C⁻¹
C) J/kg
D) W/mK
85.
The temperature at which Fahrenheit and Celsius scales are equal is: A) -40°
B) 0°
C) 40°
D) 100°
86.
The Fahrenheit freezing point of water is: A) 0°F
B) 32°F
C) 100°F
D) 212°F
87.
The Fahrenheit boiling point of water is: A) 100°F
B) 180°F
C) 212°F
D) 273°F
88.
The greenhouse effect is related to: A) Heat retention
B) Heat loss
C) Expansion
D) Conduction
89.
The sun’s energy is produced mainly by: A) Combustion
B) Fusion
C) Fission
D) Radiation only
90.
The SI unit of latent heat is: A) J/kg
B) J/K
C) W
D) N
91.
A perfect black body is: A) Perfect absorber
B) Perfect reflector
C) Transparent body
D) Insulator
92.
The rate of heat transfer by conduction increases with: A) Larger area
B) Greater temperature difference
C) Better conductivity
D) All of these
93.
Heat required to raise temperature depends on: A) Mass
B) Specific heat
C) Temperature change
D) All of these
94.
A calorie is defined as heat needed to raise: A) 1 kg water by 1°C
B) 1 g water by 1°C
C) 100 g water by 1°C
D) 10 g water by 1°C
95.
Which state has the greatest molecular motion? A) Solid
B) Liquid
C) Gas
D) Plasma
96.
The thermal equilibrium condition is described by: A) Zeroth law of thermodynamics
B) First law
C) Second law
D) Third law
97.
The first law of thermodynamics is based on: A) Conservation of mass
B) Conservation of energy
C) Momentum conservation
D) Gravitation
98.
The SI unit of internal energy is: A) Joule
B) Watt
C) Kelvin
D) Newton
99.
A body at higher temperature has: A) Greater average kinetic energy
B) Greater mass
C) Greater volume always
D) Lower energy
100.
Heat transfer by convection cannot occur in: A) Solids
B) Liquids
C) Gases
D) Fluids
Answer Key (Heat)
1-B, 2-C, 3-B, 4-C, 5-C, 6-B, 7-B, 8-C, 9-B, 10-A
11-B, 12-C, 13-C, 14-A, 15-A, 16-C, 17-B, 18-A, 19-C, 20-B
21-C, 22-C, 23-C, 24-D, 25-D, 26-A, 27-C, 28-C, 29-B, 30-B
31-C, 32-B, 33-A, 34-B, 35-C, 36-C, 37-B, 38-C, 39-A, 40-C
41-A, 42-B, 43-A, 44-B, 45-B, 46-B, 47-A, 48-A, 49-C, 50-B
51-A, 52-A, 53-B, 54-C, 55-A, 56-C, 57-C, 58-A, 59-C, 60-D
61-B, 62-C, 63-C, 64-A, 65-C, 66-A, 67-C, 68-C, 69-B, 70-B
71-D, 72-B, 73-B, 74-B, 75-A, 76-B, 77-B, 78-A, 79-C, 80-B
81-A, 82-C, 83-A, 84-B, 85-A, 86-B, 87-C, 88-A, 89-B, 90-A
91-A, 92-D, 93-D, 94-B, 95-C, 96-A, 97-B, 98-A, 99-A, 100-A