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Question
A football player hits the ball with a speed of 20 m s-1 with an angle of 30° with respect to horizontal direction as shown in the figure. The goal post is at a distance of 40 m from him. Find out whether the ball reaches the goal post?
Solution
Given:
Initial speed (u) = 20 ms-1
The angle of projection (θ) = 30°
The distance of the goal post = 40 m
Solution:
Range of the projectile R = `(u^2 sin2theta)/g = (400 xx sin 60^circ)/9.8 = (400 xx sqrt3/2)/9.8` = 35.35 m
The distance of the goal post is 40 m. But the range of the ball is 35.35 m only. So the ball will not reach the goal post.
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