Mechanical energy is the sum of kinetic and potential energy in an object.
We are given that At 2.5 seconds, the helicopter has a kinetic energy of 20 J, Also we know that Energy per time is called the power and is the rate of energy, therefore in order to find the mechanical energy at that time, we will simply divide the values, thus:
Mechanical energy is given as:
[tex]ME=\frac{20J}{2.5sec}=8 joules per second[/tex]
Thus, the mechanical energy will be 8 joules per second.
