It takes 20 s for a person A of mass 50 kg to climb up the stairs, while another person B of same mass does the same in 15 s. </br>Compare the </br>(i) work done and </br>(ii) power developed by the persons A and B.

Question

It takes 20 s for a person A of mass 50 kg to climb up the stairs, while another person B of same mass does the same in 15 s.
Compare the
(i) work done and
(ii) power developed by the persons A and B.

April 9, 2024

Answer

(i) We know that work done is a product of force and displacement and is independent of time. Hence both persons A and B will do the same amount of work.

Therefore, a ratio of work done by A and B = 1:1

(ii) The power developed by the persons A and B :

We know that Power = work done / time

Work done is the same by A and B

Time A took = 20 s

Time B took = 15 s

Therefore, more power is spent by B as B does the work at a faster rate.

Substituting the values in the formula we get :

Power = 1 / time

Power spent by A : Power spent by B = 15 : 20

⇒ Power spent by A : Power spent by B = 3 : 4

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Question

It takes 20 s for a person A of mass 50 kg to climb up the stairs, while another person B of same mass does the same in 15 s. Compare the (i) work done and (ii) power developed by the persons A and B.

Answer

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Flash Education

It takes 20 s for a person A of mass 50 kg to climb up the stairs, while another person B of same mass does the same in 15 s.
Compare the
(i) work done and
(ii) power developed by the persons A and B.