(adsbygoogle = window.adsbygoogle || []).push({}); rotational motion, energy conservation problem URGENT please help

1. The problem statement, all variables and given/known data

A uniform rod of mass M=2 kg and length L = 2m is pivoted from its end. It has a point mass m=1 kg on its tip. It stars from rest at an angle of 30 degrees above horizontal. It falls under the influence of gravity. How fast is the tip m moving when the rod is horizontal at θ

= 0

2. Relevant equations

mgh = 1/2mv^2

3. The attempt at a solution

h= Lsinθ = 1

m cancels from both sides

so you're left with

v=√2g=4.42

BUT, the actual answer given is 4.8

Help please! I have a test in just a few hours and have been trying to figure this problem out for awhile! Thanks

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# Homework Help: Rotational motion, energy conservation problem please help

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