A worker pushes a heavy crate along a rough warehouse floor. Explain why work is done on the crate and describe what happens to the energy that is transferred due to the friction between the crate and the floor.

AQA GCSE Physics (8463) — 4.5.2 Work done and energy transfer · Explain · 4 marks · View as Markdown

Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).

A worker applies a horizontal force to push a heavy crate along a rough warehouse floor for several metres.

Model answer (4 marks)

Work is done because the worker applies a horizontal force to the crate and the crate moves in the direction of that force.
The amount of work is the force multiplied by the distance over which it acts.
This work is done against the frictional force between crate and floor.
The energy transferred by this work is converted into heat, raising the temperature of the crate and/or the floor.

Examiner tips

  • Use the definition of work (F×d) and state the direction condition; mention friction explicitly; explain energy conversion to heat; keep answer concise to fit 4 marks.

Common mistakes

  • Saying work is done only if the force is perpendicular to motion; forgetting to mention friction; describing energy as ‘lost’ without specifying heat.

Mark scheme (4 marks)

  1. Work is done because a force is applied to the crate and the crate moves in the direction of that force
  2. Work done is equal to force multiplied by distance moved
  3. Work is done against friction / work is done against frictional forces
  4. Work done against friction causes a rise in temperature of the crate and/or floor

Key terms in this question

friction

Related

More Work done and energy transfer questions

▶ Try answering this question with AI marking (free) →