Question

A solid cylinder of mass $M$ and radius $R$ rolls without slipping down an inclined plane making an angle $\theta$ with the horizontal. the force of friction acting on the cylinder is

• A. $\frac{2}{3} Mg\, sin\,\theta$
• B. $\frac{1}{3} Mg\, sin\,\theta$
• C. $\frac{2}{5} Mg\, sin\,\theta$
• D. $\frac{2}{7} Mg\, sin\,\theta$

Answer 1

Answer: (B)

Force of friction, $f = Mg\,sin\,\theta - Ma$
$ = Mg \, sin \, \theta - \frac{2}{3} Mg \, sin\, \theta $
$= \frac{1}{3}Mg \,sin\,\theta$