How much should a weight of 4 kg be lowered down so that its potential energy decreases by 100 J?

Given:

m = 4 kilograms – the mass of a certain load;

E = 100 Joules – the amount by which the potential energy of this load has decreased;

g = 10 N / kg (Newton per kilogram) – acceleration due to gravity (rounded off).

It is required to determine h (meter) – how much you need to lower the load down so that its potential energy decreases by the value of Q.

To determine the change in the height of the load, you must use the following formula:

E = m * g * h, from here we find that:

h = E / (m * g) = 100 / (4 * 10) = 100/40 = 10/4 = 2.5 meters.

Answer: the load must be lowered by 2.5 meters.