Kicking a Field Goal: Initial Speed Needed for Clear Crossbar

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To determine the initial speed required for a field goal to clear a crossbar at a height of 3.05 m from a distance of 10.98 m when kicked at an angle of 53 degrees, the relevant equations of motion must be applied. The horizontal motion can be described using the equation x(t) = Vox * t, while the vertical motion is given by y(t) = Voy * t - 0.5 * g * t^2. By substituting the expressions for Vox and Voy in terms of the initial speed and angle, the problem can be solved without needing the exact initial velocity. The key is to use the known distance and height to find the time of flight and subsequently the initial speed. Understanding these relationships is crucial for solving projectile motion problems effectively.
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Homework Statement


If the ball is kicked at 53 degrees above horizontal what must the initial speed be if it is just to clear the crossbar. I know the ball is distance in the x direction is 10.98 m and the height of the goal post is 3.05 m.


Homework Equations


I think I should be using the equations Voy=Vosin(theta) and Vox=Vocos(theta)


The Attempt at a Solution


No idea how to solve without having any veclocities to plug into the above equations.
 
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Welcome to the PF. I moved your thread from Advanced Physics to Introductory Physics.

You have listed two of the equations that you will need to solve the problem. Now list the equation for motion x(t) in the horizontal direction, in terms of Vx(t) and Vox and t. And list the equation for motion in the vertical direction y(t), in terms of Vy(t) and Voy and t and the acceleration of gravity g.

With those equations of motion, and the ending (x,y) point you are given, do you see how you may not need to know the initial velocity Vo?
 
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