Show that when a body is dropped from a certain height, the sum of its kinetic energy at any instant during its fall is constant

cbse
cbse-class-9-science
work-and-energy

#1

Show that when a body is dropped from a certain height, the sum of its kinetic energy at any instant during its fall is constant.
Answer:
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The mechanical energy (kinetic energy + potential energy) of a freely falling object remains constant. It may be shown by calculation as follows:
Suppose a body of mass m falls from point A, which is at height ‘H’ from the surface of earth. Initially at point A, kinetic energy is zero and the body has only potential energy.
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