**EXAMPLE 2: ****Euler's 2nd law for 2-D motion**

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The uniform bar of mass *m* and length *l* is released from rest in the horizontal
position. Calculate the equation of its angular velocity as a function of the
angle of rotation.

**Solution:**

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_{}

_{}

_{}

This
is the equation of motion for the bar. We must integrate it to get the angular
velocity _{}.

_{}

_{}

_{}

The
constant of integration C is evaluated using the initial condition _{}

at _{} to give C=0.
Therefore,

_{}

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