the gravitational potential energy of a ball is 20 J when the ball is dropped. If mechanical energy is conserved, which energies are possible for the ball as it falls

Standing side by side ,you and a friend step off a bridge at different times and fall for 1.6s to the water below.your friend goes first,and you follow after he has dropped a distance of 2.0m.when your friend hits the water,is the seperation between the two of you 2.0m or more than 2.0m? verify your answer with a calculation.

Hydrogen and helium are both members of?

Chemical energy is a form of energy. a. heat b. kinetic c. potential d. electromagnetic