Question

A 1.000 kg boulder rolls 75 m down a mountain doing 735,000 J of work.
What force was acting on the boulder?​

Answer 1

Answer:

9800 N

Explanation:

The work done by the boulder is equal to the product between the force acting on it and the distance covered by the boulder:

$W=Fd$

where

F is the magnitude of the force

d is the distance covered by the boulder

Here we know

W = 735,000 J is the work done

d = 75 m

Solving the equation for F,

$F=\frac{W}{d}=\frac{735000}{75}=9800 N$

This force is actually equal to the force of gravity acting on the boulder, which is given by:

$F=mg$

where

m = 1000 kg is the mass of the boulder

$g=9.8 m/s^2$ is the acceleration of gravity

Substituting,

$F=(1000)(9.8)=9800 N$