Question

A body is moving along a rough horizontal surface with an initial velocity $6\, ms^{-1}$ If the body comes to rest after travelling a distance $9\, m$, then the coefficient of sliding friction will be

• A. 0.4
• B. 0.2
• C. 0.6
• D. 0.8

Answer 1

Answer: (B)

0.2

Answer 2

Given : $u=6\, m / s,\, s=9\, m,\, v=0$ From equation of motion $v^{2} =u^{2}-2 as$ $0=(6)^{2}-2 \times a \times 9$ $18\, a=36$ $\Rightarrow a=2\, m / s ^{2}$ Coefficient of sliding friction is given by $\mu =\frac{a}{g}$ $=\frac{2}{10}=0.2$