Beginning physics question about solving for time using kinematic equations?

AI Thread Summary
To solve for the height of a racket ball when it leaves the racket, the horizontal distance of 2.15 m and the speed of 5.37 m/s are used to calculate time using the formula time = distance / speed. The user encounters issues when attempting to apply 2-Dimensional kinematic equations, leading to incorrect time calculations. Clarification is sought on whether the final horizontal velocity (Vx) should be considered as 0 or 5.37 m/s. The discussion emphasizes the importance of correctly applying kinematic equations and understanding the components of motion. Accurate interpretation of these equations is crucial for solving the problem effectively.
JohnApplebee
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Homework Statement



A racket ball is struck in such a way that it leaves the racket with a speed of 5.37 m/s in the horizontal direction. When the ball hits the court, it is a horizontal distance of 2.15 m from the racket. Find the height of the racket ball when it left the racket.


Homework Equations



Kinematic equations


The Attempt at a Solution




I already have the solution BUT it's because I solved for time using the formula time = distance / speed. However, I tried solving for time using the 2-Dimensional kinematic equations involving acceleration (-9.8), time, Inital velocity, etc. I plugged in all the variables except for time and my answer for time came out way wrong. So why is that? What am I doing wrong? Thanks.
 
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And just wondering: would final velocity of x (Vx) = 0 or 5.37?
 
JohnApplebee said:
What am I doing wrong?
I don't know. If you show your work maybe I could say.

And just wondering: would final velocity of x (Vx) = 0 or 5.37?
If you were hard-pressed to think about it, which would you say and why?
 
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