-
A man throws balls with the same speed vertically upwards one after the other at an interval of 2 seconds. What should be the speed of the throw so that more than two balls are in the sky at any time? [Given g = 9.8 m/s²]
-
- Only with speed 19.6 m/s
- More than 19.6 m/s
- At least 9.8 m/s
- Any speed less than 19.6 m/s
Correct Option: B
Let the required speed of throw be u ms–1. Then time taken to reach maximum height,
t = u/g
For two balls to remain in air at any time, t must be greater than 2.
| ∴ | > 2 ⇒ u > 19.6 m/s | |
| g |
