A ball is rolled off the edge of a swimming pool and strikes the water 2.0 m away 0.30 seconds later. What was the initial speed of the ball? its speed when it strikes the water?

Question

anonymous · Answer

How do I solve for this?

anonymous · Answer

You can calculate what the height of the pool edge is from the amount of time it took the ball to hit the water, that would be a good start.

anonymous · Answer

What formula would I use for the height of the pool?

anonymous · Answer

Under a certain acceleration 'a', the distance an object travels in a certain time 'dt' is:
$$s=\frac{1}{2} a dt^2$$

anonymous · Answer

so s=0.882m ?

cwrw238 · Answer

the horizontal component of the velocity will be constant

speed = distance / time = 2 / 30  ms-1

anonymous · Answer

Hint: The initial speed of the ball will be Zero..you can find the final speed (max. speed)
by using $$s=V*t$$

anonymous · Answer

I believe you forgot the 0.5 :)
@cwrw238 That would indeed give you the initial velocity, I was trying to complete the picture as the height of the pool will be needed for the second part of the picture :)
@stgreen The 2.0 meters is a horizontal measure I believe, or isnt it @danielle02

anonymous · Answer

of the question*

cwrw238 · Answer

i think it must have had an initial velocity > zero otherwise it woudn't have travelled a horizontal distance of 2 m

cwrw238 · Answer

right timsmit

anonymous · Answer

@TimSmit  yes, it is the horizontal measure

cwrw238 · Answer

sorry it was 0.30 secs not 30

anonymous · Answer

where's that 0.5 comming from? @TimSmit

anonymous · Answer

0.5 is the acceleration

anonymous · Answer

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