state the principle of conservation of mechanical energy and illustrale in case of freely falling body
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Answer:
Principle: The total mechanical energy of a system is conserved i.e., the energy can neither be created nor be destroyed; it can only be internally converted from one form to another if the forces doing work on the system are conservative in nature.
Law of conservation of energy states that the energy will neither be created nor destroyed however is reworked from one type to a different.
Let us currently prove that the on top oflaw holds smart within the case of a freely falling body.
Let a body of mass 'm' placed at a height 'h' on top of the bottom, start falling down from rest.
In this case we've got to indicate that the overall energy (potential energy + kinetic energy) of the body at A, B and C remains constant i.e, potential energy is
completely transformed into kinetic energy.
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At A, Potential energy = mgh
Kinetic energy mechanical energy = zero[the speed is zero because the object is ab initio at rest]
Total energy at A = mechanical energy + mechanical energy
Total energy at A = mgh …(1)
At B, Potential energy = mgh
= mg(h - x) [Height from the bottom is (h - x)] mechanical energy = mgh - mgx
Kinetic energy The body covers the space x with a speed v.
We create use of the third equation of motion to get speed of the body.
v2 - u2 = 2aS
Kinetic energy = mgx
Total energy at B = mechanical energy + mechanical energy
Total energy at B = mgh …(2)
At C, mechanical energy = m x g x zero (h = 0)
Potential energy = 0 Kinetic energy
The distance coated by the body is h v2 - u2 = 2aS
Kinetic energy
Kinetic energy = mgh
Total energy at C = mechanical energy + mechanical energy = zero + mgh
Total energy at C = mgh …(3) it's clear from equations one, two and three that the overall energy of the body remains constant at each purpose.
Thus, we have a tendency to conclude that law of conservation of energy holds smartwithin the case of a freely falling body.