Flatcar Hoop Problem: Find Ball's Initial Velocity

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AI Thread Summary
A man on a flatcar traveling at 9.10 m/s needs to throw a ball through a hoop 4.90 m high, using a throw speed of 10.8 m/s relative to himself. The vertical component of the ball's initial velocity must be calculated to ensure it reaches the hoop while moving horizontally. The discussion highlights confusion regarding the correct application of kinematic equations and the relationship between vertical and horizontal motion. Participants suggest clarifying the problem statement and emphasize that only the vertical component is needed for the ball to reach the height of the hoop. The conversation underscores the importance of accurately interpreting physics problems for effective problem-solving.
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Homework Statement


A man is riding on a flatcar traveling at a constant speed of 9.10m/s. He wishes to throw a ball through a stationary hoop 4.90m above the height of his hands in such a manner that the ball will move horizontally as it passes through the hoop. He throws the ball with a speed of 10.8m/s with respect to himself. What must the vertical component of the initial velocity of the ball be?


Homework Equations


y=y0+v0t+1/2gt^2
y=4.9?? ..not sure if that's right
y0=0
g=9.8

The Attempt at a Solution


i am pretty sure y=4.9
using this i solved t=v0/g
then i plugged what i had into the relevant equation
and i got v0=5.65 which is way off

please help! thanks!
 
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Very awkward stated question but w/e.

What is the speed the vertical component when it only has a horizontal velocity?
 
i didn't write the question. it is very awkwardly stated though. would it be 0 since there is only horizontal direction?
 
Ok then just think about it like how much velocity you need to throw a ball 4.9m. Since the horizontal doesn't matter.

You might want to write down the question exactly.
 
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