MCQ
A force $\vec{F}=3 \hat{i}+\hat{c j}+2 \hat{k}$ 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
- ✓12
- B6
- C1
✓
Answer
Correct option: A.
12
(a)$W=\vec{F} \cdot s=(3 \hat{i}+\hat{c j}+2 \hat{k}) \cdot(-4 \hat{i}+2 \hat{j}-3 \hat{k})=-12+2 c-6$Work done $=6 J$ (given)$\therefore-12+2 c-6=6 \Rightarrow c=12$
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