MCQ
A body is moving along a rough horizontal surface with an initial velocity $6\,\,m/s.$ If the body comes to rest after travelling $9\, m$, 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
(b) We know $s = \frac{{{u^2}}}{{2\mu \;g}}$
(b) We know $s = \frac{{{u^2}}}{{2\mu \;g}}$
$\therefore \mu = \frac{{{u^2}}}{{2gs}} = \frac{{{{(6)}^2}}}{{2 \times 10 \times 9}} = 0.2$
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