Friction: Bottom Most Point

Q. When a body rolls without sliding, up an inclined plane, the frictional force is

1. Directed up the plane
2. Directed down the plane
3. Zero
4. Dependent on its velocity

Q. As shown in figure, a uniform disc of mass $m$ is rolling without slipping with an angular velocity $\omega$. The portion $AB$ is rough and $BC$ is smooth. If the disc crosses point $B$, the motion of the disc will be:

1. translational motion only
2. pure rolling motion
3. rotational motion only
4. none of these