A disc of radius R rolls on a rough horizontal surface. The distance covered by the point A in one revolution is

A disc of radius R rolls on a rough horizontal surface. The distance c

1.	A disc of radius R rolls on a rough horizontal surface. The distance covered by the point A in one revolution is
Answer» `2 PI R` 2R 8R `PIR` Solution :Path of A is cycloid and distance TRAVELLED in ONE rotation is 8R.