Question

What is the work done on a box if a force of 20.0N is applied at an angle of -25.0° while the box moves 8.00m?159J145J-67.6J21.2J

Answer 1

The work done by a constant force in a rectilinear motion is given by:

$W=Fd\cos\theta$

where F is the magnitude of the force, d is the distance the object moves and θ is the angle between the force vector and the displacement vector. In this case we have that:

0. The magnitude of the force is 20 N

,

1. The distance is 8 m

,

2. The angle between the force and the displacement vector is -25°.

Plugging these values in the expression for the work we have:

$\begin{gathered} W=(20)(8)\cos(-25) \\ W=145 \end{gathered}$

Therefore, the work done on the box is 145 J