Projectile motion in serious need of help

AI Thread Summary
A user is seeking help with a physics problem involving projectile motion for an upcoming test. The scenario involves a place-kicker kicking a football from 36.0 m away at a speed of 20.0 m/s and an angle of 53.0°. The user initially struggles with calculating the time to reach the goal and the height of the ball at that time. After guidance, they successfully determine the correct answer regarding whether the ball clears the crossbar and its trajectory. The discussion highlights the importance of understanding projectile motion concepts and applying them to solve real-world problems.
DJ-Smiles
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I need loads of help, i have a physics test on friday and have been studying vigorously; i haven't been lazy and have been working fopr 8 weeks, i tried to do this question and i have no clue HELP ME PLEASE!

Homework Statement



A place-kicker must kick a football from a point
36.0 m (about 40 yards) from the goal, and half the crowd
hopes the ball will clear the crossbar, which is 3.05 m high.
When kicked, the ball leaves the ground with a speed of
20.0 m/s at an angle of 53.0° to the horizontal. (a) By how
much does the ball clear or fall short of clearing the crossbar?
(b) Does the ball approach the crossbar while still rising
or while falling?

The Attempt at a Solution


Ok so i found the velocity of the x component using simple trig but then I am in trouble with the next step. i have absolutely no clue at all i tried to find the time it takes to cover the x displacemetn at the x velocity then used that time to find the overall displacement.
 
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Solve the y displacement instead using the time you got. The time you got is the time at which the ball is at x = 36.0 m, so the next step would be to calculate the height of the ball at that time. Then compare that height to the height of the crossbar and answer question a.
 
thank you sooo much You honestly don't know how much that means i was stressing out big time because the test is thursday and I am fixing up my weaker points...

I did what you said and the answer is correct

Once again thanks so much
 
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