A ball rolls down an inclined plane as shown in figure. The ball is first released from rest from P and then later from Q. Which of the following statement is/are correct? (i) The ball takes twice as much time to roll from Q to O as it does to roll from P to O. (ii) The acceleration of the ball at Q is twice as large as the acceleration at P. (iii) The ball has twice as much K.E. at O when rolling from Q as it does when rolling from P.

Question

G1 Physics · Accepted Answer

The acceleration down a fixed incline is independent of the starting point, so statement ii is false. From Q the travel distance is twice that from P, so time increases by √2, not by 2; statement i is false. The drop in height is doubled, so the final kinetic energy at O doubles; statement iii is true. Hence option D.