Online Test — Heat and Temperature
25 Questions • 15 min • Chapter MCQ
15:00
Question 1 of 25
Heat is best described as a:
Measure of hotness
Form of energy
Type of force
Type of light
Explanation: Heat is a form of energy that flows from hot to cold.
Question 2 of 25
Temperature is a measure of:
Total energy
How hot or cold an object is
Mass
Volume
Explanation: Temperature measures the degree of hotness of an object.
Question 3 of 25
Heat flows from an object at ______ temperature to one at ______ temperature.
Lower; higher
Higher; lower
Equal; equal
Zero; high
Explanation: Heat flows from higher temperature to lower temperature.
Question 4 of 25
The SI unit of heat is the:
Kelvin
Joule
Newton
Pascal
Explanation: Heat is a form of energy, so its SI unit is the joule (J).
Question 5 of 25
A cup and a bucket of water are both at 100 °C. The bucket has:
Lower temperature
More heat energy
Less heat energy
No heat
Explanation: The bucket has more water (particles), so it holds more heat at the same temperature.
Question 6 of 25
A common liquid thermometer works on the principle of:
Reflection
Expansion of a liquid with heat
Magnetism
Friction
Explanation: The liquid expands when heated and rises, indicating the temperature.
Question 7 of 25
A clinical thermometer is used to measure the temperature of the:
Air
Human body
Boiling water
Ice
Explanation: A clinical thermometer measures human body temperature.
Question 8 of 25
On the Celsius scale, the boiling point of water is:
0 °C
100 °C
212 °C
273 °C
Explanation: Water boils at 100 °C on the Celsius scale.
Question 9 of 25
On the Kelvin scale, water freezes at:
0 K
100 K
273 K
373 K
Explanation: Water freezes at 273 K on the Kelvin scale.
Question 10 of 25
The kink in a clinical thermometer is used to:
Increase the range
Hold the reading after removal
Cool the liquid
Measure pressure
Explanation: The kink stops the liquid flowing back, holding the reading.
Question 11 of 25
The Celsius and Kelvin scales are related by:
K = C − 273
K = C + 273
K = C × 273
K = 273 − C
Explanation: Kelvin = Celsius + 273.
Question 12 of 25
To convert Celsius to Fahrenheit, use:
F = (9/5)C + 32
F = (5/9)C − 32
F = C + 273
F = C − 32
Explanation: F = (9/5) × C + 32 converts Celsius to Fahrenheit.
Question 13 of 25
27 °C in Kelvin is:
27 K
300 K
246 K
273 K
Explanation: K = C + 273 = 27 + 273 = 300 K.
Question 14 of 25
100 °C in Fahrenheit is:
100 °F
180 °F
212 °F
273 °F
Explanation: F = (9/5)(100) + 32 = 180 + 32 = 212 °F.
Question 15 of 25
The combined relation between scales is:
C/9 = (F−32)/5 = K
C/5 = (F−32)/9 = (K−273)/5
C = F = K
C/5 = F/9 = K/273
Explanation: The scales are related by C/5 = (F−32)/9 = (K−273)/5.
Question 16 of 25
The transfer of heat through a solid without the solid moving is called:
Convection
Conduction
Radiation
Reflection
Explanation: Conduction is heat transfer through a solid by particles passing energy.
Question 17 of 25
Heat transfer in liquids and gases by the movement of the fluid is called:
Conduction
Convection
Radiation
Refraction
Explanation: Convection transfers heat by the actual movement of the heated fluid.
Question 18 of 25
Heat transfer that needs no medium and can occur through a vacuum is:
Conduction
Convection
Radiation
Insulation
Explanation: Radiation needs no medium and is the only mode that works through a vacuum.
Question 19 of 25
The Sun's heat reaches the Earth mainly by:
Conduction
Convection
Radiation
Friction
Explanation: The Sun's heat crosses the vacuum of space by radiation.
Question 20 of 25
Which of these is a good conductor of heat?
Wood
Plastic
Metal
Air
Explanation: Metals are good conductors of heat; wood, plastic, and air are insulators.
Question 21 of 25
Most substances, when heated, will:
Contract
Expand
Stay exactly the same
Disappear
Explanation: Most substances expand when heated and contract when cooled.
Question 22 of 25
A bimetallic strip bends on heating because its two metals:
Have the same expansion
Expand by different amounts
Do not expand
Melt
Explanation: The two metals expand by different amounts, so the strip bends.
Question 23 of 25
The heat needed to raise the temperature of a substance is given by:
Q = mcΔT
V = IR
F = ma
P = F/A
Explanation: Q = m c ΔT gives the heat needed (mass × specific heat × temperature change).
Question 24 of 25
The heat absorbed when a substance changes state without a temperature change is called:
Specific heat
Latent heat
Thermal expansion
Conduction
Explanation: Latent heat is the heat involved in changing state at constant temperature.
Question 25 of 25
Water is used as a coolant because it has a high:
Density
Specific heat capacity
Colour
Speed
Explanation: Water's high specific heat lets it absorb much heat with little temperature rise.