Law of Conservation of Energy

 

Law of Conservation of Energy

 

Statement:

 

The law of conservation of energy states that “Energy may neither be created nor destroyed, it can only change shape”

 

Explanation:

Consider a body of mass “m” at height “h” above the ground. Its kinetic energy

 

at that point A is:

 

K.E = 1/2(mv2)

 

K.E = 1/2 m * (o)

 

K.E = o…………..(i)

 

The potential Energy at point A is:

 

P.E = mgh …………(ii)

 

So the total energy at point A will be:

 

T.E = K.E + P.E

 

E(A) = O + mgh

 

E(A) = mgh

 

 

Suppose the body is released from this height and falls through a distance x. Its new height will be (h-x]. The velocity with which it reaches point B is calculated by using the third equation of motion:

 

2gs = Vf2 – Vi2

 

As we know:

 

Vi = 0

S = x

 

Therefore,

2gx = Vf2 – 0

2gx = v2

 

The kinetic energy at point B is:

 

K.E. = 1/2 mv2

 

Substituting the value of v2:

 

K.E.= 1/2*m * 2gx

 

K.E = mgx

 

The Potential Energy at point B is:

 

P.E = mgh

 

The height of the body is (h-x):

 

P.E. = mg(h-x)

 

The total energy at point B is: y

 

E(B) = PE + K.E.

 

E(B) = max + mg(h-x)

E(B) = mgx + mgh -mgx

 

E(B) = mgh

 

Hence, the total energy at point A and B are some. It means that the total value of energy remains constant.

 

I note right away that the classification and characteristics described below are rather arbitrary. The advantages of one could be attributed to the disadvantages of the other and vice versa. And by and large, there are a lot of reservations that I did not mention, because and so the chapter probably turned out to be quite long and even somewhat boring.