What is the initial projectile speed of the ball?

1. Jan 13, 2007

kappcity06

The pitcher in a slow-pitch softball game releases the ball at a point 3.0 ft above ground level. A stroboscopic plot of the position of the ball is shown in the figure below, where the readings are 0.25 s apart and the ball is released at t = 0. On the horizontal axis, x1 = 20 ft.

(a) What is the initial speed of the ball?
ft/s
(b) What is the speed of the ball at the instant it reaches its maximum height above ground level?
ft/s
(c) What is that maximum height?
ft

i tried to find part c first. since i know that time is equal to 1.25 seconds i used deltay=.5at^2
.5(32)(1.25)^2
25 feet
this did not work so I do not know what to do?
any one with any help. thaks

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2. Jan 13, 2007

hage567

Why are you using t=1.25s in your calculation? That isn't the time it takes the ball to get to maximum height.

3. Jan 13, 2007

Dorothy Weglend

Dorothy

4. Jan 14, 2007

Gib Z

u=0 i think

5. Jan 14, 2007

cristo

Staff Emeritus
u can't be zero as the ball is pitched!

6. Jan 14, 2007

kappcity06

i am still not getting the answer. I also tried time as 1.25/2 but this is stil not right?