Projectile motion in serious need of help

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SUMMARY

The discussion focuses on solving a projectile motion problem involving a place-kicker kicking a football from a distance of 36.0 meters at an initial speed of 20.0 m/s and an angle of 53.0° to the horizontal. The key steps include calculating the horizontal and vertical components of the velocity, determining the time to reach the goal, and finding the vertical displacement at that time to compare with the crossbar height of 3.05 meters. The final solution confirms that the ball clears the crossbar, addressing both parts of the homework question effectively.

PREREQUISITES
  • Understanding of projectile motion principles
  • Knowledge of trigonometric functions for resolving velocity components
  • Ability to apply kinematic equations for motion analysis
  • Familiarity with the concept of vertical displacement in projectile motion
NEXT STEPS
  • Study the derivation of projectile motion equations
  • Learn how to calculate horizontal and vertical components of velocity
  • Explore kinematic equations for vertical motion in physics
  • Practice solving similar projectile motion problems with varying angles and speeds
USEFUL FOR

Students preparing for physics exams, particularly those focusing on projectile motion concepts, as well as educators seeking to reinforce these principles in their teaching materials.

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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