Finding initial vertical velocity given acceleration

AI Thread Summary
To find the initial vertical velocity of a shot put heaved upward with a constant acceleration of 45.4 m/s², the problem states that the shot is released at a height of 2.16 m after accelerating for 0.65 m. The correct approach involves using the kinematic equation V² = initial V² + 2a(x - initial x). The user initially calculated the final velocity at the highest point as zero, which is incorrect since the final velocity at release is not zero. The calculations suggest that the initial velocity is approximately 7.68 m/s, but there may be a misunderstanding in interpreting the problem's parameters.
freshyy
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Homework Statement


Sam heaves a shot with weight 16-lb straight upward, giving it a constant upward acceleration from rest of 45.4 m/s^2 for a height 65.0 cm . He releases it at height 2.16 m above the ground. You may ignore air resistance.

Q-What is the speed of the shot when he releases it?

Homework Equations

: [/B]
Equations I believe I can use are
V=initial V +at or
V^2=initial V^2 +2a(x-initial x)

The Attempt at a Solution


Since the final velocity would be zero when it is at the highest point i got
0=initial V^2 +2(45.4m/s^2)(-.65m)
I would have V ^2=59.02
then V=7.68m/s
but this says it is wrong when i check my answer.
Please help
 
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freshyy said:
Since the final velocity would be zero when it is at the highest point i got
The final velocity is the velocity when he releases it--that's not zero. It starts at zero.

Nonetheless, the equation is correct and so is your answer. Are you sure you are posting the exact problem?
 
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