# Help needed with this physics problem!

I only have really started physics and I need help with this problem for homework.Any help is much appreciated!

A football is kicked from the
floor in a 7.00 m high
sports hall with an initial speed of 20.0 m/s. What is the maximum horizontal
distance it can
fly without touching the ceiling until it strikes the
floor?

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HallsofIvy
Have you drawn a a picture? Let $\theta$ be the angle the initial velocity vector makes with the floor. Do you know how to find the horizontal and vertical components of velocity in terms of $\theta$? There is no acceleration horizontally, so horizontal velocity stays is constant. Do you know how to find the horizontal distance the ball will go in t seconds?
That will depend on $\theta$.) The value of x for that t is the horizontal distance the ball flies- that will also depend on $\theta$.
You want to find the value of $\theta$ that maxizes that distance with the restriction that the height of the ball is always less than 7 meters.