Question

A 20-kg barrel is rolled up a 20-m ramp to the back of a truck whose floor is 5.0 m above the ground. What work is done in loading one barrel into the truck?

Answer 1

The angle of inclination is calculated using sin function,

sin θ = 5 m / 20 m = 0.25

θ = 14.4775°

The net force exerted is then calculated:
F net = m g sin θ = 20 * 9.8 * 0.25

F net = 49N

Work is product of net force and distance:
W = F net * d = 49 * 20

Work = 980 J