Question

If it takes 20 N to move a box, how much power will be needed to move the box a distance of 5 meters in 5 seconds?

Answer 1

Power is work done per time and work done is force times distance. The power is found by multiplying the force(20N) and the distance(5m) and dividing the product by the time(5s)
(20*5)/5=20Nm/s OR 20 watts.
Therefore the power needed is 20 watts.

Answer 2

It will need 20 Watts power to move the box 5 meters in 5 seconds.

Explanation:

The power is defined as the work per unit time or the rate of doing work:

W=dL/dt

Where de work L, can be calculated by multiplying the force by the displacement d:

L=F.d

To this example, F and D are known, therefore the work is:

L=20N . 5m=40 Nm

We know that the work is doing within a time of 5 seconds:

W= 40 Nm / 5s = 20 Nm/s = 20 Watts