Find energy lost in a system.

Question

A projectile of mass 0.6 kg is shot straight up with an initial speed of 17.5 m/s. How much energy is lost from the system if it reaches a max height of 13.78125?

Answer 1

Subtract its final potential energy (when it is instantaneously at rest) from its initial kinetic energy (when the potential energy is zero).  That will be the energy lost.

 

lost energy = mv²/2 - mgh = ?

 

Plug in the given values for m, v, and h, and get your answer.  (By the way, you did not state the units of h).