MCQ
If force $(\vec{F})=4 \hat{i}+5 \hat{j}$ and displacement $(\vec{s})=3 \hat{i}+6 \hat{k}$ then the work done is
- ✓$4 \times 3$
- B$5 \times 6$
- C$6 \times 3$
- D$4 \times 6$
✓
Answer
Correct option: A.
$4 \times 3$
(a) $W=\vec{F} \vec{S}=(4 \hat{i}+5 \hat{j})(3 \hat{i}+6 \hat{j})=12$
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