A wooden block of mass 2 ,kg is dragged 4.0 ,m along a rough horizontal floor by a…
PHYSICS · Subjective · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A wooden block of mass 2\,kg is dragged 4.0\,m along a rough horizontal floor by a constant pull of 25\,N acting at an angle of 37∘ above the horizontal. The coefficient of kinetic friction between the block and the floor is 0.20. Take g=10m s−2.
(a) Calculate the work done by each of the following forces during the displacement:
(i) the applied pull,
(ii) kinetic friction,
(iii) the weight of the block,
(iv) the normal reaction of the floor.
(b) Determine the net work done on the block.
(c) Using the result of (b), find the speed of the block at the end of the displacement if it started from rest.