Determine the mechanical energy of this object: a 1-kg ball sits on a 10-meter high cliff.

a. the ball isn't moving, so the mechanical energy is zero
b. 10 j
c. 98 j
d. 980 j

also could you explain how you did it because i have know idea how to solve it

Acoil formed by wrapping 80 turns of wire in the shape of a square is positioned in a magnetic field so that the normal to the plane of the coil makes an angle of 28.0° with the direction of the field. when the magnetic field is increased uniformly from 200 µt to 600 µt in 0.400 as, an emf of magnitude 80.0 mv is induced in the coil. what is the total length of the wire?

Aforce is a vector quantity because it has both?

James joule carefully measured the difference in temperature of the water at the top and bottom of a waterfall. why did he expect a difference