Question

Determine the mechanical energy of this object: 1-kg ball rolls on the ground at 2 m/s

A. The ball is on the ground, so the mechanical energy is zero
B. 2 J
C. 1 J
D. 4 J

Answer 1

Mechanical energy = potential energy + kinetic energyThe ball is on the ground so has no potential energy.
M.E = K.EM.E = 1/2 mv²M.E = 1/2 x 1 x 2²M.E = 2 J