Question
Define angular acceleration.
✓
Answer
It can be expressed as the rate of change of angular velocity with respect to time i.e.
$\alpha=\frac{d \vec{\omega}}{d t}$
If the rotation axis is constant then the direction of $\vec{\omega}$ and hence the direction of $\vec{\alpha}$ will also be constant. Inthis situation the vector equation changes into a scalar equation and we can write it in the following way :
$\alpha=\frac{d \omega}{d t}$
$\alpha=\frac{d \vec{\omega}}{d t}$
If the rotation axis is constant then the direction of $\vec{\omega}$ and hence the direction of $\vec{\alpha}$ will also be constant. Inthis situation the vector equation changes into a scalar equation and we can write it in the following way :
$\alpha=\frac{d \omega}{d t}$
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