To solve this problem we must rely on the equations of the simple harmonic movement that define the period as a function of length and gravity as
Where
l = Length
g = Gravity
Re-arrange to find L,
Our values are given as
Replacing,
Therefore the height would be 25.348m
The bowling ball is at rest, so it only has gravitational potential energy.
Ug = mgy
Ug = (2)(9.8)(40) = 784 J
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