MCQ
A body is moving along a rough horizontal surface with an initial velocity $6 \mathrm{~m} / \mathrm{s}$. If the body comes to rest after travelling $9 \mathrm{~m}$, then the coefficient of sliding friction will be
- A$0.4$
- ✓$0.2$
- C$0.6$
- D$0.8$
✓
Answer
Correct option: B.
$0.2$
(b) We know $s=\frac{u^2}{2 \mu g} $
$ \therefore \mu=\frac{u^2}{2 g s}=\frac{(6)^2}{2 \times 10 \times 9}=0.2$
$ \therefore \mu=\frac{u^2}{2 g s}=\frac{(6)^2}{2 \times 10 \times 9}=0.2$
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