When the velocity of the body is doubled and the mass is halved the K.E will be:
Correct answer: B. Doubled
- A. Unchanged
- B. Doubled
- C. Halved
- D. Four times
Explanation
K.E = 1/2 mv^2(K.E)' = 1/2 (m/2) (2v)^2 = 1/2 (m/2) 4v^2 = 2 (1/2 mv^2) = 2 (K.E)
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Work transfers energy when a force causes displacement, while kinetic energy, gravitational potential energy and power describe motion, position and the rate of energy transfer. The work-energy theorem links net work with change in kinetic energy, and efficiency accounts for energy losses rather than treating them as energy destruction.
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