Respuesta :

Answer:

 E_g = m 392 J,      Ek = m 392

Explanation:

Mechanical energy is a very important concept since if the system does not have friction it remains constant

the potential energy of a system is

          E_g = U = m g (y2 - i)

          E_g = m 9.8 (40 -0)

          E_g = m 392 J

The kinetic energy for this system assuming it started from rest

          E_k = K = ½ m v2

how mechanical energy is conserved

         E_g = E_k

         Ek = m 392