A woman pushes a lawn mower with a con-

Question

stant force of 112 Newtons at an angle of
37degrees with respect to the horizontal. The lawn mower moves at a speed of 20 cm/sec.
What is her power output? (1 hp = 746
Watts)

Answer 1

Fp = Fh = 112cos37 = 89.48N = Force parallel to the plane.

Po = Fp*V = 89.48 * 0.2m/s = 17.9W.

hp = Po/746 = 17.9 / 746 = 0.024.