1-Balls thrown by a juggler: A juggler performs in a room whose ceiling is at a height h(adsbygoogle = window.adsbygoogle || []).push({});

above the level of his hands. He throws his first ball vertically upwards so that it just

reaches the ceiling. At the instant when this happens, he throws his second ball upward

with the same initial speed.

(a) With what initial speed does he throw his first ball?

(b) How much time is required for this ball to reach the ceiling?

(c) How long a time after the second ball is thrown do the two balls pass each other?

(d) How far above the juggler’s hands are the balls when they pass each other?

2-A football kicker can give the ball an initial speed of v . Within what two elevation angles

must he kick the ball to score a field goal from a point at a distance L to the front of

goalposts whose horizontal bars is at a height h above the ground?

(Hint use sin^2θ + cos^2θ = 1 to get a relation between 2 tan^2θ and

1/cos^2θ substitute

and then solve the quadratic equation)

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# Homework Help: With what initial speed does he throw his first ball?

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