# 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 15 Hz?

Dec 15, 2016

The angular momentum is $= 80 \pi = 251.3 k g {m}^{2} {s}^{- 1}$

#### Explanation:

The angular momentum is

$L = I \omega$

The moment of inertia of a rod is $I = \frac{1}{12} m {l}^{2}$

$I = \frac{1}{12} \cdot 8 \cdot 4 = \frac{8}{3} k g {m}^{2}$

The angular velocity is $\omega = 15 \cdot 2 \pi r a {\mathrm{ds}}^{- 1}$

So,

$L = \frac{8}{3} \cdot 30 \pi k g {m}^{2} {s}^{- 1} = 80 \pi k g {m}^{2} {s}^{- 1}$