How much work does it take to lift a #180 kg # weight #3/2 m #?
Gravitational potential energy is given by the equation,
#m#is the mass of the object in kilograms
#g#is the gravitational acceleration, which is around #9.8 \ "m/s"^2#
#h#is the height in meters
And so, we get:
work = force times distance.
First, to overcome the gravitational pull on the weight, you need to exert a force upwards on it that is equivalent to the gravitational force:
now the weight does not move, but there's a net force of 0 on it. It is neither going up or down.
Then you move it up through a course of
You can also think of it this way: Energy is a conserved quantity, which means that it is neither destroyed nor created. Thus it can only be transferred from one form to another. Work is the measure of how much energy is transferred from one form to another.
In this case as the weight is being lifted, the kinetic energy it gained from the force you exert on it, is converted to its gravitational potential energy. When it is at
So its gravitational potential energy went from 0 at ground level to