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It Takes 20 S for a to Climb up the Stairs, While B Does the Same in 15 S. Compare the (I) Work Done, and (Ii) Power Developed by a and B.

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Question

It takes 20 s for A to climb up the stairs, while B does the same in 15 s. compare the (i) work done, and (ii) power developed by A and B.
Numerical
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Solution

(i) work done depends on the displacement, now, vertical distance travelled by A and B is same, hence ratio of wok done by them is 1 : 1.

(ii) Power = `"work done"/"time taken"`

      `"P"_"A"/"P"_"E" = 1/1 xx 15/20 = 3/4`

The required ratio is 3 : 4.

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Chapter 1: Force, Work, Energy and Power - Exercise 1.4 iii [Page 39]

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Frank Physics Part 2 [English] Class 10 ICSE
Chapter 1 Force, Work, Energy and Power
Exercise 1.4 iii | Q 4 | Page 39

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