Projectile Motion baseball Problem

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J-dizzal
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Homework Statement


In the figure, a baseball is hit at a height h = 1.30 m and then caught at the same height. It travels alongside a wall, moving up past the top of the wall 1.1 s after it is hit and then down past the top of the wall 3.9 s later, at distance D = 42 m farther along the wall. (a) What horizontal distance is traveled by the ball from hit to catch? What are the (b) magnitude and (c) angle (relative to the horizontal) of the ball's velocity just after being hit? (d) How high is the wall?

http://edugen.wileyplus.com/edugen/...u/ch0/EAT_13496164302600_3698173899564502.GIF

Homework Equations


r(t)=r0+v0t+1/2 at2

The Attempt at a Solution


im having trouble finding v0 in the x direction I am getting 15m/s=42m/2.8s
[/B]
20150628_121738_zps9yo8uleq.jpg
 
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J-dizzal said:

Homework Statement


In the figure, a baseball is hit at a height h = 1.30 m and then caught at the same height. It travels alongside a wall, moving up past the top of the wall 1.1 s after it is hit and then down past the top of the wall 3.9 s later, at distance D = 42 m farther along the wall. (a) What horizontal distance is traveled by the ball from hit to catch? What are the (b) magnitude and (c) angle (relative to the horizontal) of the ball's velocity just after being hit? (d) How high is the wall?

http://edugen.wileyplus.com/edugen/...u/ch0/EAT_13496164302600_3698173899564502.GIF

Homework Equations


r(t)=r0+v0t+1/2 at2

The Attempt at a Solution


im having trouble finding v0 in the x direction I am getting 15m/s=42m/2.8s[/B]

Your calculations already contain an error.

The ball initially clears the top of the wall 1.1 s after it is hit, according to the problem statement. The ball then travels 42 m before it drops below the top of the wall, 3.9 s later.

You have assumed that the ball drops below the top of the wall 3.9 s after it is hit, which I don't think is what the problem says happens. :wink:
 
SteamKing said:
Your calculations already contain an error.

The ball initially clears the top of the wall 1.1 s after it is hit, according to the problem statement. The ball then travels 42 m before it drops below the top of the wall, 3.9 s later.

You have assumed that the ball drops below the top of the wall 3.9 s after it is hit, which I don't think is what the problem says happens. :wink:
that should help. let me try this again. thanks