Free Falling Bodies: Calculating Time for Wrecking Ball

AI Thread Summary
The discussion revolves around calculating the time it takes for a wrecking ball to fall to the ground after its cable breaks. The initial suggestion is to use the formula t = (vfinal - vinitial) / g, but there is confusion about determining the final velocity. Another participant recommends using the equation X = Xinitial + vt + 0.5at^2, with acceleration set to -9.8 m/s². The initial position is identified as 0, and the halfway point as 0.5, but there is uncertainty about finding the initial velocity since the ball starts from rest. The conversation highlights the need for clarity on how to derive the necessary variables for the calculations.
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Homework Statement


A wrecking ball is hanging at rest from a crane when suddenly the cable breaks. The time it takes for the ball to fall halfway to the ground is 1.31sex. Find the time it takes for the ball to fall from rest all the way to the ground.

I think the formula to use is t=vfinal-vinitial / g
But not sure what vfinal is to use this formula so I am stuck...
 
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Hey dude try using this formula: X=X+vt+0.5at^2 :biggrin:
 
with that formula
a=-9.8
t=1.31sec
where would the X come from??
 
Xfinal=Xinitial + vt + 0.5at^2. i believe you know Xinitial?
 
I believe the x initial is 0 and xfinal is .5 since it's half way but not sure how I would find "v" from the question so that I can find "t"
 
the v is vinitial so what should the initial velocity of something that is at rest be?
 

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