Question

In the figure, s sphere of radius $2m$ rolls on a plank. The accelerations of the sphere and the plank are indicated. The value of $\alpha$ is

• A. $2rad/s^2$
• B. $4rad/s^2$
• C. $3rad/s^2$
• D. $1rad/s^2$

Answer 1

The correct option is C $3rad/s^2$

Acceleration of point A must be equal to the acceleration of the plank due to pure rolling.

$\alpha r-a_2=a_1$

$\alpha \left(2\right)-4=2⟹\alpha =3rad/s^2$