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.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
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.
Practise Work and Energy
748 free Work and Energy MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Work and Energy questions
Which of the following type of force cannot do work on which it acts?
Power can be defined as the dot product of:
A man pulling a bag with force of 15 N at angle 60° with horizontal plane. If bag convers a distance of 10 m, then work done by the man is:
If velocity is double, then:
A ball is dropped from a height as shown.Ignoring the effects of air resistance, the total energy is:
A machine which has an efficiency of 80% raises a load of 50N through a vertical height of 10m. The work input to the machine is: