Question

A chain couples and rotates two wheels in a bicycle. The radii of bigger and smaller wheels are $0.5m$ and $0.1m$ respectively. The bigger wheel rotates at the rate of $200$ rotations per minute, then the rate of rotation of smaller wheel will be:

• A. $1000rpm$
• B. $\frac{50}{3}rpm$
• C. $200rpm$
• D. $40rpm$

Answer 1

Answer: (A)

$1000rpm$

As the linear velocities remains constant, using $v=r\omega$ we get $r_1{\omega }_1=r_2{\omega }_2$
$\Rightarrow 0.1{\omega }_1=0.5\times 200$
$\Rightarrow {\omega }_1=1000rpm$