(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 16.00 lead sphere is hanging from a hook by a thin wire 3.20 long, and is free to swing in a complete circle. Suddenly it is struck horizontally by a 5.50 steel dart that embeds itself in the lead sphere.

What must be the minimum initial speed of the dart so that the combination makes a complete circular loop after the collision?

2. Relevant equations

3. The attempt at a solution

1) i've try equating T = mv^2 / r = mg when the sphere reaches the top of the swing.

v=5.6 as r = 3.2 and m cancels out.

2) then initial p = final p

5.5 v = (16+5.5) (5.6)

i'll get initial v of 21.9m/s for the dart but its wrong.

can anyone tell me what's wrong? or should i just the mgh PE at the top approach?

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# Homework Help: Dart strikes lead sphere

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