![A point mass is shot vertically up from ground level with a velocity of 4 m/s at time, t = 0](https://www.gkseries.com/blog/wp-content/uploads/2023/10/A-point-mass-is-shot-vertically-up-from-ground-level-with-a-velocity-of-4-m-s-at-time-t-0-.jpg)
Q. A point mass is shot vertically up from ground level with a velocity of 4 m/s at time, t = 0 . It loses 20% of its impact velocity after each collision with the ground. Assuming that the acceleration due to gravity is 10 m/s2 and that air resistance is negligible, the mass stops bouncing and comes to complete rest on the ground after a total time (in seconds) of
(A) 1 (B) 2 (C) 4 (D) ∞
Ans: 4