A force of 100 lb acts 45 degrees positive counter clockwise

A force of 100 lb acts 45 degrees (positive counter clockwise) on a particle that is constrained to move in a straight line to the right. If the particle, which starts from rest, moves 10 ft to the right how much total work is done on the particle?

Solution

Work done = force * displacement

Force = 100 cos 45 = 70.71 lb ( in the direction of displacement)

W D = 70.71* 10 = 707.1 lb-ft