Well i recently came across a question on rotational-
A cylinder of radius r rolls without slipping over a horizontal plane . two points a and b at a particular instant are located on the cylinder. a on vertically top point and b on the right hand side edge of the diameter.
they asked to find the radius of curvature of trajectory of a and b.
the suggested method was of a cycloid. i dont know how to do it.pls help............also suggest an easier method if u have any