Q. 53.7( 6 Votes )
A body is falling freely under the action of gravity alone in vacuum. Which of the following quantities remain constant during the fall?
A. Kinetic energy.
B. Potential energy.
C. Total mechanical energy.
D. Total linear momentum.
During free fall,
K.E. increases, momentum increases and P.E. decreases
Total mechanical energy=K.E.+P.E.
As P.E. decreases and K.E. increases ∴ M.E. remains constant.
Option (c) is correct.
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