Answer:
Hydroelectricity is a renewable energy source.
Hydroelectricity increases the stability and reliability of electricity system
Hydroelectricity helps fight climate changes.
Explanation:
If we use hydroelectricity our country would be in good climate and not a bad one. And the best facts it is renewable.
Answer: 7840N
Explanation:
Given that
Potential energy = ?
Mass of sled = 20-kg
Distance = 40 meters
Acceleration due to gravity = 9.8m/s^2
Recall that potential energy is the energy possessed by a body at rest
i.e potential energy = mass m x acceleration due to gravity g x distance h
P.E = mgh
P.E = 20kg x 9.8m/s^2 x 40m
P.E = 7840N
Thus, the potential energy of the sled is 7840N
By measuring the expansion of the substance. In that case you use a thermometer
