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Standard VII

Physics

Speed

Question 11 A...

Question

Question 11
Avinash can run with a speed of $8 m s^{- 1}$ against the frictional force of $10 N$ , and Kapil can move with a speed of $3 m s^{- 1}$ against the frictional force of $25 N$ . Who is more powerful and why?

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Solution

$P o w e r = \frac{W o r k d o n e}{T i m e} = \frac{F o r c e \times d i s t a n c e}{T i m e} = F o r c e \times V e l o c i t y$
$\Rightarrow$ $P = F \times v$
Power of Avinash $= P_{A} = F_{A} \times v_{A} = 10 \times 8 = 80 W$
Power of Kapil $= P_{K} = F_{K} \times v_{K} = 25 \times 3 = 75 W$
So, Avinash is more powerful than Kapil, because he does more work against the frictional force than kapil.

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Q. Question 11
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Question 11 Avinash can run with a speed of 8 ms−1 against the frictional force of 10 N, and Kapil can move with a speed of 3 ms−1 against the frictional force of 25 N. Who is more powerful and why?

Power=Work doneTime=Force×distanceTime=Force×Velocity ⇒P=F×v Power of Avinash =PA=FA×vA=10×8=80 W Power of Kapil =PK=FK×vK=25×3=75 W So, Avinash is more powerful than Kapil, because he does more work against the frictional force than kapil.

Question 11
Avinash can run with a speed of $8 m s^{- 1}$ against the frictional force of $10 N$ , and Kapil can move with a speed of $3 m s^{- 1}$ against the frictional force of $25 N$ . Who is more powerful and why?