Question

A cylinder rolls up an inclined plane, reaches some height and then rolls down (without slipping through these motion). The direction of the frictional force acting on cylinder are

• A. Up the incline while ascending and down the incline while descending
• B. Up the incline while ascending as well as descending
• C. Down the incline while ascending and up the incline while descending
• D. Down the incline while ascending as well as descending

Answer 1

The correct option is B Up the incline while ascending as well as descending

While ascending the cylinder tries to pull the ground backwards while moving forward, thus frictional force acts upwards. During descending the frictional force again acts upwards. If friction were absent the body would slide down. Thus the frictional force in this case is responsible for rolling motion of the cylinder