(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A rugby ball of mass 400 grams is to be kicked from ground level to clear

a crossbar 3m high. The goal line is 12m from the ball, and the junior

rugby player can impart a maximum speed of 4√g ms−1 to the ball.

(a) Modelling the ball as a projectile moving under gravity alone, what is

the minimum launch angle that will succeed? What is the range of

the ball when launched at this angle and speed?

3. The attempt at a solution

Not quite sure how to approach this one at all. The ball would need to go high enough, from the initial vertical speed given to it - 4√g.sinθ. That by the time it reaches the crossbar in a time we can calculate from its horizontal component, it is exactly 3m above the ground. I get the feeling I am missing something though.

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# Homework Help: 2D motion

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