Question

state law of consuervation of energy of freely falling body???

Answer 1

Mass is same for all
At point A :
height = h
gravity = g
so, potential energy = mgh
Now, kinetic = 1/2mv²
as v = 0
kinetic energy = 1/2 m * 0² = 0
TOTAL ENERGY = P + K =mgh

Now, at point b:
potential energy = mgh
h = h- x
so potential energy = mg(h-x)
kinetic energy = 1/2mv²
v² - u² =2gx
v² = 2gx
so, total energy = p +k =mgh
Now, at point C :
potential energy = 0
as h = 0
kinetic energy = 1/2mv'²
v'² - u² =2gh
v'² = 2gh
kinetic energy = mgh
so, total energy = mgh
In all three point energy is conserved as at all point energy is mgh.

Answer 2

Energy can neither be created nor destroyed. It can only be converted from one form to the other.