questionpaper

• Which two sentences describe the movement of the air particles in the canister?

  they move in random directions

  they move with a range of different speeds
• The temperature of the air inside the canister increases. What happens to the movement of the air particles?

  the kinetic energy increases
• It could be dangerous if the temperature of the air inside the canister increased by a large amount. Explain why.

  the pressure increases so it could explode
• cavity wall insulation is installed in the wall of a house. Explain how the wall reduces unwanted energy transfers.

  the wall has two / three layers cavity

  wall insulation/brick/block has a low thermal conductivity

  so less energy is transferred by conduction
• Explain how the readings on both meters change when the environmental conditions change.

  • resistance of LDR changes when light intensity changes

  • when light intensity increases resistance of LDR decreases

  • overall resistance of the circuit decreases

  • potential difference across total resistance remains unchanged

  • current in ammeter increases

  • potential difference across fixed resistor increases