A force F⃗ = 3î + cĵ + 2k̂ acting on a par

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A force $\vec F = 3\hat i + c\hat j + 2\hat k$ acting on a particle causes a displacement $\vec S = - 4\hat i + 2\hat j - 3\hat k$ in its own direction. If the work done is $6J$, then the value of $c$ will be

A

$12$

B

$6$

C

$1$

D

$0$

A force $\vec F = 3\hat i + c\hat j + 2\hat k$ acting on a particle causes a displacement $\vec S = - 4\hat i + 2\hat j - 3\hat k$ in its own direction. If the work done is $6J$, then the value of $c$ will be

$W = \overrightarrow F .\overrightarrow s = (3\hat i + c\hat j + 2\hat k).( - 4\hat i + 2\hat j - 3\hat k)$$ = - 12 + 2c - 6$

Work done $ = 6J$ (given)

$\therefore $ $ - 12 + 2c - 6 = 6$$ \Rightarrow $ $c = 12$