A box is pushed 5 m along a floor and back again to its start. The work done against friction is:

  1. not zero — it is twice the one-way work
  2. negative
  3. zero
  4. equal to the change in PE
Answer

A) not zero — it is twice the one-way work

Friction opposes motion in both directions. SLO P-11-B-31 · Understanding

Physics MCQ · More Work and Energy MCQs · Practise