A person "X" of 75 kg walks up a staircase in 15 s. Another person "Y" of mass 60 kg walks up the same staircase in 12s. The ratio of the power generated by "X" to that by "Y" is:
Correct answer: D. 1
- A. 4/5
- B. 5/4
- C. 5/6
- D. 1
Explanation
To find the power generated by each person, we use the formula: P = mgh/t, where m is mass, g is gravitational acceleration (constant for both), h is height (same for both as they climb the same staircase), and t is time taken.For person X: Px = 75 * g * h / 15For person Y: Py = 60 * g * h / 12The ratio of their powers is given by: Px/Py = (75/60) * (12/15)Simplifying this gives: Px/Py = 1, meaning the power is equal for both, hence the correct answer is 1.Options A, B, and C are incorrect because they do not match the calculated ratio based on the given data.
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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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