A 4 kg block moving at 5 m/s slides 5 m along a rough floor against a friction force of 6 N. Its final kinetic energy is:

  1. 50 J
  2. 30 J
  3. 80 J
  4. 20 J
Answer

D) 20 J

Work–energy theorem: Kf = Ki - fd = 50 - 30 = 20 J. SLO P-11-B-32 · Application

Physics MCQ · More Work and Energy MCQs · Practise