Predicted Questions

• At point B, the child has landed on the trampoline. At point C, the child is at his lowest point relative to the ground. The springs of the trampoline have extended before the child is launched back up again (3)

  • B, maximum kinetic energy
  • B to C, kinetic energy converted to elastic potential energy
  • C, minimum kinetic energy, maximum elastic potential in springs
• Explain the effect of increasing temperature on thermistor. (2)

  • Increasing temp decreases resistance
  • higher temp provides more energy to the electrons, more to move freely and carry current
• Connecting the resistors in parallel would decrease the total resistance of the circuit. Why (1)

  in parallel circuits, each resistor provides alternative path for current, this increases total current for same potential difference
• Describe the structure of an alpha particle (1)

  2 protons and 2 neutrons
• Explain, in terms of particle motion, how the gas inside the football creates pressure. (2)

  • gas particles in the football move due to their kinetic energy
  • when particles collide with football walls, force is exerted. Pressure if force per unit area
• Same volume of gas inside football is slowly compresses into a smaller, sealed container while keeping the temperature constant. Explain what happens to the pressure of the gas (2)

  • pressure of the gas increases
  • smaller area for particles to move so there are more frequent collisions
• explain why expanding a gas rapidly causes a decrease in temperature (2)

  • when gas expands rapidly, particles do work on surroundings as they move apart
  • work requires energy which is taken form kinetic energy of the particles, leading to a decrease in temperature