Projectile motion (ground to ground)

[J-dizzal]

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

I have the kinematic equations and equations for motion (while in flight)

The Attempt at a Solution

known solns:
a_y = -g = -9.8m/s²
v_0y = 29.89 m/s
v_fy = -29.89 m/s
Δy = 0
t= 6.1s

im stuck at this point. i think maybe i can set the v at max height equal to the x component of v₀?[/B]

 

[haruspex]

Consider its horizontal velocity for the time it is above the wall.

 

[J-dizzal]

Consider its horizontal velocity for the time it is above the wall.

velocity for the time the ball is over the wall,
v = Δd/Δt
= 42m / 3.9
= 10.77m/s.
But this is average velocity, if a_x is constant and v_x is constant then the avg velocity is equal to v at any point?

Then,
v_avg = v_0x = v₀cosθi,
is the x component of v₀.

Thanks.
How do you type unit vecotors i,j, and k with hats?

 

[haruspex]

velocity for the time the ball is over the wall,
v = Δd/Δt
= 42m / 3.9
= 10.77m/s.
But this is average velocity, if a_x is constant and v_x is constant then the avg velocity is equal to v at any point?

Then,
v_avg = v_0x = v₀cosθi,
is the x component of v₀.

Thanks.
How do you type unit vecotors i,j, and k with hats?

Yes.
For the hat, use Latex. Putting a consecutive pairs of hash symbols(#) starts and ends a Latex string. Using dollar symbols instead puts the Latex on a line of its own. A hat over a character is achieved by writing \hat in front of it. Put a space after hat. If it is to go over something more complicated than a single character, use curly brackets: \hat{x^2} will produce ##\hat{x^2}##.
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