1. 1
   A delivery worker pushes a loaded trolley 12 m across a flat warehouse floor by applying a constant horizontal force of 60 N, overcoming friction between the trolley's wheels and the floor.

   (a)

   Which equation should be used to calculate the work done by the worker on the trolley?

   [1 mark]

   • AW = F × d
   • BW = m × g
   • CW = ½ × m × v²
   • DW = F/t

   (b)

   As the trolley moves, friction acts between its wheels and the warehouse floor. Which form of energy transfer occurs because of this friction?

   [1 mark]

   • ASome energy is transferred to the surroundings by heating
   • BSome energy is transferred usefully to gravitational potential energy
   • CSome energy is transferred to elastic potential energy in the wheels
   • DNo energy is transferred; friction has no energy effect

   (c)

   Calculate the work done by the delivery worker in pushing the trolley 12 m with a force of 60 N, and explain what this calculated value represents in terms of energy transferred.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   At a fairground, an operator stretches the elastic cords of a catapult-style ride before releasing them to launch a rider upwards into the air.

   (a)

   At a fairground, an operator stretches the elastic cord of a bungee-style catapult ride before releasing it to launch a rider upwards. While the cord is stretched, what type of energy is stored within it?

   [1 mark]

   • AKinetic energy
   • BGravitational potential energy
   • CElastic potential energy
   • DThermal energy

   (b)

   The operator uses cords with a greater spring constant for a more powerful launch. Which equation would the operator use to calculate the elastic potential energy stored in a cord of known spring constant and extension?

   [1 mark]

   • AE_e = ½ × k × e²
   • BE_e = m × g × h
   • CE_e = ½ × m × v²
   • DE_e = F × d

   (c)

   One of the cords has a spring constant of 400 N/m and is stretched by 2.5 m before release. Calculate the elastic potential energy stored in this cord, and explain what happens to this energy as the cord is released and the rider is launched upwards.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A tower crane on a construction site lifts a steel beam of mass 800 kg vertically upwards to a height of 15 m above the ground, at a steady speed, taking 20 seconds to complete the lift.

   (a)

   Calculate the gravitational potential energy gained by the beam (take gravitational field strength as 10 N/kg), and state the equation used.

   [3 marks]

   (b)

   Using the gravitational potential energy gained by the beam and the time taken for the lift, calculate the power output of the crane's motor during the lift, and explain what 'power' means in this context.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A road safety authority is running a campaign near a primary school to persuade drivers to slow down from 30 mph to 20 mph in residential streets during school opening and closing times.

   (a)

   A road safety authority is running a campaign near a school to persuade drivers to slow down from 30 mph to 20 mph in residential areas. Explain, using the equation for kinetic energy, why a relatively small reduction in a car's speed from 30 mph to 20 mph produces a much bigger reduction in the car's kinetic energy than the change in speed alone would suggest, and explain the significance of this for road safety near schools.

   [6 marks]

   (b)

   The campaign also compares a family car with a much heavier delivery van travelling at the same speed near the school. Explain, using the kinetic energy equation, how the mass of the vehicle affects its kinetic energy at a given speed, and explain why this means speed limits may need to be considered alongside the types of vehicles using a road, not just the road's general speed limit.

   [6 marks]

   Total for question 4: 12 marks

End of questions