Question

A solid sphere rolls down on two different inclined planes of same height, but of different inclinations. In both cases

• A. speed and time of descent will be same
• B. speed will be same, but time of descent will be different
• C. speed will be different, but time of descent will be same
• D. speed and time of descent both are different

Answer 1

Answer: (B)

speed will be same, but time of descent will be different

Answer 2

In pure rolling, mechanical energy remains conserved. Therefore, when heights of inclines are equal, speed of sphere will be same in both the cases. But as acceleration down the plane, $a \propto \sin \theta$ therefore, acceleration and time of descent will be different.