A force vec F = (5hat{i} + 3hat{j})N is applied over a particle which displaces it from its original

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5.Work, Energy, Power and Collision

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A force $\vec F = (5\hat i + 3\hat j)\;N$is applied over a particle which displaces it from its original position to the point $\vec s = (2\hat i - 1\hat j)$m. The work done on the particle is.........$J$

A

$+ 11 $

B

$+ 7$

C

$+ 13$

D

$-7 $

Solution

(b)$W = \overrightarrow F .\overrightarrow s $$ = (5\hat i + 3\hat j).(2\hat i – \hat j)$$ = 10 – 3$ = $7\,J$

Standard 11

Physics

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