The question is: A body of mass m moving with velocity v has a kinetic energy K. If its velocity is increased by 25%, what will be the new K.E?
Correct answer: A. 25/16 K
- A. 25/16 K
- B. 23/34 K
- C. 12/45 K
- D. 34/58 K
Explanation
The kinetic energy of a body is given by:K.E = 1/2 * m * v^2Where:K.E is the kinetic energym is the mass of the bodyv is the velocity of the bodyIf the velocity is increased by 25%, the new velocity will be 1.25v.The new kinetic energy will be:New K.E = 1/2 * m * (1.25v)^2 = 1/2 * m * 1.5625v^2 = 1.5625 * (1/2 * m * v^2)Therefore, the new kinetic energy is 1.5625 times the original kinetic energy.This can be expressed as 25/16 K
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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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