# What is the angular momentum of a rod with a mass of  8 kg and length of 4 m that is spinning around its center at 9 Hz?

Feb 17, 2016

$L = 192 \cdot \pi$

#### Explanation:

$L \text{ :Angular momentum}$
$\omega \text{ :Angular velocity}$
$I \text{ :moment of inertia of rod}$
$\text{Angular momentum for a rotating object is given by: L=} I \cdot \omega$
$\omega = 2 \cdot \pi \cdot f$
$I = \frac{1}{12} \cdot m \cdot {l}^{2} \text{ (for rod rotating around its center)}$
$L = \frac{1}{12} \cdot m \cdot {l}^{2} \cdot 2 \cdot \pi \cdot f$
$L = \frac{1}{12} \cdot 8 \cdot {4}^{2} \cdot 2 \cdot \pi \cdot 9$
$L = 192 \cdot \pi$