MCQ
A body is pulled along a rough horizontal surface with a velocity $6\,m/s$. If the body comes to rest after travelling $9\,m$ , then coefficient of sliding friction, is- (Take $g = 10\,m/s^2$ )
- ✓$0.2$
- B$0.4$
- C$0.5$
- D$0.6$
✓
Answer
Correct option: A.
$0.2$
a
$s=\frac{v^{2}}{2 u_{k} g}$
$s=\frac{v^{2}}{2 u_{k} g}$
$\Rightarrow \mu_{\mathrm{k}}=\frac{\mathrm{v}^{2}}{2 \mathrm{sg}}=\frac{6 \times 6}{2 \times 9 \times 10}=0.2$
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