MCQ
If a force $\vec{F}=4 \hat{i}+5 \hat{j}$ causes a displacement $\vec{s}=3 \hat{i}+6 \hat{k}$, work done is
- A$4 \times 6$ unit
- B$6 \times 3$ unit
- C$5 \times 6$ unit
- ✓$4 \times 3$ unit
✓
Answer
Correct option: D.
$4 \times 3$ unit
(d) $W=\vec{F} \cdot s=(4 \hat{i}+5 \hat{j}+0 \hat{k}) \cdot(3 \hat{i}+0 \hat{j}+6\hat{k})=4 \times 3$ units
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