Question
A player P kicks the football with velocity 20 m/s at angle of 15°. Another player Q on the goal line 12 m away in the direction of kick, runs at the same instant to meet the ball. With what speed he should run so that he could catch the ball just before it hits the ground? (Take g = 10 m/s2).
Solution
We know that,
Horizontal range,
We have,
∴
Horizontal range,
i.e. the ball hits the ground at a distance of 20m from the position of player P.
Since the player Q is 12m away, therefore, he has to travel a distance 8m to catch the ball in time equal to the time of flight.
Now the time of flight is,
The velocity of player Q is,