Mechanical energy formula
Mechanical energy is the total amount of kinetic energy and potential energy of an object used to do a particular task. Mechanical energy can also be defined as the energy of an element due to the position and/or movement of the element. The potential energy of an object comes from its position, and the kinetic energy comes from its movement. The potential energy when the object is moving is zero, and the kinetic energy when the object is stationary is zero.
Formula
M.E = K.E + P.E
M.E = ½ mv2 + mgh
Here,
m= mass of an object
v= velocity of that object
g= acceleration due to gravity
h= height of an object
Solved examples
The man sits in a 20m high building and weighs 50kg. Calculate mechanical energy?
The given parameters are:
m = 50 kg
h = 20 m
Since the man does not move, the equation for K.E = 0
mechanical energy
M.E = 1/2 mv2 + mgh
K.E is 0, so the equation is as follows. ,
ME = mgh
ME = 50 × 9.81 × 20
ME = 9810 J