Answer:
Change in potential energy = 7350 Joules
Explanation:
It is given that,
Side of cube, a = 0.5 m
Density of cube, 
The cube is lifted vertically by a crane to a height of 3 m
We know that, density 
So, m = d × V (V = volume of cube = a³)

m = 250 kg
We have to find the change in potential energy of the cube. At ground level, the potential energy is equal to 0.
Potential energy at height h is given by :

PE = 250 kg × 9.8 m/s² ×3 m
PE = 7350 Joules
So, change in potential energy of the cube is 7350 Joules.
If you are working with electricity most people will measure it in watts.
So, A. watts is your best answer.
Hope I helped! ^w^
There would be more - charges on the peanuts because they gain electrons which are represented with the - sign. There would also be more + on the cat to show that the cat’s fur is positively charged. The peanuts would be attracted to the cat because opposite charges attract.
As for explaining the first model, there should be the same amount of + and - charges on the peanuts as well as the cat to show that it is balanced and the peanuts are not attracted or repelled by the cat.
Thew energy stored in a capacitor of capacitance
and voltage between the plates
is
.
Substituting numerical value
