Thermal Physics

What happens to the temperature of water when it reaches its boiling point?

• It fluctuates between boiling and freezing.
• It continues to rise indefinitely.
• It drops immediately.
• It remains constant until all water has evaporated.

What is the main purpose of a heat engine?

• To measure temperature changes.
• To convert heat energy into work.
• To cool down substances.
• To store thermal energy.

Which of the following statements is true regarding heat transfer?

• Heat can only be transferred through conduction.
• Heat flows from cold to hot objects.
• Heat flows from hot to cold objects.
• Heat transfer does not occur in liquids.

When heat is added to a substance, what effect does it have on the motion of its particles?

• The particles move faster.
• The particles stop moving.
• The particles move slower.
• The particles move in a circular motion.

Which of the following best describes the process of calorimetry?

• Measuring the heat transfer during physical and chemical changes.
• Determining the pressure of gases in a closed container.
• Measuring the speed of sound in different materials.
• Calculating the density of various substances.

What is the principle of calorimetry based on?

• The heat lost by a hot body equals the heat gained by a cold body.
• Heat is always lost to the surroundings.
• Heat transfer occurs only in gases.
• Heat can only be transferred from cold to hot.

In a calorimeter, what is the purpose of polishing its outside surface?

• To prevent heat from entering.
• To increase the heat capacity.
• To reduce heat loss to the surroundings.
• To make it look attractive.

What is the latent heat of a substance?

• The heat absorbed or released during a phase change.
• The heat needed to start a chemical reaction.
• The heat required to change its temperature.
• The heat lost to the surroundings during cooling.

How does the specific heat capacity of water compare to that of most other substances?

• It is higher than that of most substances.
• It is lower than that of most substances.
• It varies widely among different substances.
• It is the same as that of most substances.

What is the formula used to calculate the quantity of heat required to change the temperature of a substance?

• Q = mcΔT
• Q = m + c + T
• Q = m/cT
• Q = mc/T