Question

If it takes 68 joules of work to push a desk chair across a floor, what force would be needed?

Answer 1

Well it depends...

Explanation:

Work is given by the equation `W=Fxxd`, where `F` is the force applied in newtons, and `d` is the distance in meters.

If you just give `W=68 \ "J"`, there are infinitely many solutions to

`F*d=68`

So, it also depends on the distance the desk is pushed.

Answer 2

`F=68/sN`

Explanation:

`W=Fs`, where:

• `W` = work done (`J`)
• `F` = force (`N`)
• `s` = distance travelled in the direction of the force (`m`)

The question only gives the value for `W` and not `s`, so `F` can only be given in terms of `s`.

`F=W/s=68/sN`