IGCSE Thermal Physics Quiz

A gas is contained in a sealed container in a laboratory. The temperature of the gas increases. What happens to the average speed and what happens to the total kinetic energy of the gas molecules?

• average speed does not change, total kinetic energy does not change

• average speed does not change, total kinetic energy increases

• average speed increases, total kinetic energy does not change

• average speed increases, total kinetic energy increases

The diagram shows the apparatus used to measure the specific latent heat of vaporisation of water. After the water begins to boil, 110 g of water is converted to steam in 120 s. Using these results, what is the value of the specific latent heat of vaporisation of water?

• 1.8 J / kg

• 1800 J / kg

• 2200 J / kg

• 2 200 000 J / kg

A block of aluminium of mass 2.0 kg has an initial temperature of 20 °C. It absorbs 7300 J of thermal energy. The specific heat capacity of aluminium is 913 J / (kg °C). What is the final temperature of the aluminium block?

• 4.0 °C

• 8.0 °C

• 24 °C

• 28 °C

The diagram shows a liquid-in-glass thermometer. Which change to the design would result in a more sensitive thermometer?

• Increase the density of the liquid.

• Increase the diameter of the capillary tube.

• Increase the number of scale markings.

• Increase the volume of the bulb.

Which statements correctly describes a liquid that is boiling

• no bubbles seen, takes place on the surface only

• no bubbles seen, takes place throughout the liquid

• bubbles seen, takes place on the surface only

• bubbles seen, takes place throughout the liquid

The liquid level in a thermometer rises when the thermometer is placed in hot water. What causes this?

• The liquid contracts.

• The liquid evaporates.

• The liquid expands.

• The liquid freezes.

A metal rod is heated at end X. Why does end Y of the metal rod become hot?

• Energy is transferred from end X of the rod to end Y by vibration of positive ions and by

  movement of electrons.

• Energy is transferred from end X of the rod to end Y by movement of positive ions only.

• Energy is transferred from end X of the rod to end Y by vibration of positive ions only.

• Energy is transferred from end X of the rod to end Y by movement of electrons only.

A student calculates the energy needed to raise the temperature of an aluminium block from 50 °C to 60 °C. He then does an experiment to measure the energy used to do this. Which statement about the measured energy is correct?

• The measured energy will be greater than the calculated energy because some energy is

  transferred to the surroundings.

• The measured energy will be greater than the calculated energy because the block absorbs

  energy from the surroundings.

• The measured energy will be less than the calculated energy because the mass of the block

  decreases as it gets warmer.

• The measured energy will be less than the calculated energy because the thermal capacity

  of the block is low.

A block of metal absorbs 2000 J of thermal energy. The temperature of the block rises from 10 °C to 20 °C. The mass of the block is 2.0 kg. What is the specific heat capacity of the metal?

• 50 J / (kg °C)

• 100 J / (kg °C)

• 200 J / (kg °C)

• 400 J / (kg °C)

Very small pollen grains are suspended in water. A bright light shines from the side. When looked at through a microscope, small specks of light are seen to be moving in a random, jerky manner.

What are the moving specks of light?

• pollen grains being hit by other pollen grains

• pollen grains being hit by water molecules

• water molecules being hit by other water molecules

• water molecules being hit by pollen grains