Question

Devin decides to start a summer job mowing lawns. In his first job, he pushes his lawn mower a total of 1.5 km. The lawn mower weighs 10 kg. During this job, Devin pushes the mower with an average force of 75N. Determine the amount of work done by Devin when mowing the lawn.

Answer 1

Answer:

$1.13\cdot 10^5 J$

Explanation:

The amount of work done by Devin when moving the lawn is given by:

$W=Fd cos \theta$

where

F is the average force applied

d is the displacement of the lawn

$\theta$ is the angle between the direction of the force and the displacement

Assuming that Devin moves the lawn by applying a force parallel to the displacement, we have:

F = 75 N

d = 1.5 km = 1500 m

$\theta=0^{\circ}$

Therefore, the work done is

$W=(75 N)(1500 m)(cos 0^{\circ})=1.13\cdot 10^5 J$