Question

A body having initial velocity of $10$m/s moving on a rough surface comes to rest after moving $50$m. What is coefficient of friction between the body and surface? $(g=10m/s^2)$

• A. $0.5$
• B. $0.2$
• C. $0.3$
• D. $0.1$

Answer 1

The correct option is D $0.1$

$Given$ :- Initial velocity of body $\left(u\right)$ = 10 $m/s$

Final velocity of body $\left(v\right)$ = 0 $m/s$

Distance covered $\left(s\right)$ = 50 $m$

Acceleration due to gravity $\left(g\right)$ = 10 ${m/s}^2$

$ToFind$ :- coefficient of friction $\left(\mu \right)$

$Solution$ :- we know, By third equation of motion , i.e,

$v^2=u^2-2as$

$100=2a\times 50$

$⟹a=1m/s^2$

Now we know , coefficient of friction $\left(\mu \right)$ is given by ,

$\mu =\frac{a}{g}$

$\therefore \mu =\frac{1}{10}⟹\underset{–}{0.1}$

Hence , $\underset{–}{OptionD\left(0.1\right)iscorrect.}$