If the speed of an object is tripled, its kinetic energy is increased by:
Correct answer: D. 9 times
- A. 1/9 times
- B. 1/3 times
- C. 6 times
- D. 9 times
Explanation
K.E = 1/2 x m x v2If mass remains constant, thenK.E ∝ v2So, if speed is tripled, thenK.E' ∝ (3)2 = 9K.E' / K.E = 9 / 1K.E' = 9 K.EK.E will increase by 9 times.
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About Work and Energy
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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