A circus joker throws vertically three balls one after another with an interval of 0.5s. After 0.5s of throwing the third ball, he catches the first. When he catches the first ball then
A-the height of the second ball is 2.5m
B-the velocity of second ball is 2.5m/s upwards
C- the height of third is 2.5m
D-the velocity of third is 2.5m/s downwards
Answers
D - the velocity of third is 2.5m/s downwards is the correct answer
Explanation:
A circus joker throws vertically three balls one after another with an interval of 0.5s. After 0.5s of throwing the third ball, he catches the first. So the position of the balls at various time period is as follows.
Assuming the joker throws the ball using his left hand and catches them using his right hand.
At 0 secs, first balls leaves the left hand.
At 0.5 secs, the first ball is at a height and travelling upward.
At 1 secs, the first ball will be at max height, no velocity upward.
At 1.5 secs, the first ball will be falling down towards the right hand.
At 2 secs, the first ball is caught by the right hand.
So when he catches the first ball, at 2 secs, the velocity of the third ball will be downwards is the right answer.
The other options are wrong because we do not know the max height here, so A and C are incorrect. And B is incorrect because there is no velocity upwards at that point.
Option D is the answer.