What is the angular momentum of a rod with a mass of #15 kg# and length of #7 m# that is spinning around its center at #19 Hz#?

1 Answer
Jan 16, 2018

The angular momentum is #=7312.1kgm^2s^-1#

Explanation:

#"Angular momentium" (kgm^2s^-1)="Moment of inertia"(kgm^2)xx"Angular velocity "(rads^-1)#

The angular momentum is #L=Iomega#

where #I# is the moment of inertia

and #omega# the angular velocity

The mass of the rod is #m=15kg#

The length of the rod is #L=7m#

The moment of inertia of a rod, rotating about the center is

#I=1/12*mL^2#

#=1/12*15*7^2= 61.25 kgm^2#

The frequency is #f=19Hz#

The angular velocity is #omega=2pif=2*19*pi=38pirads^-1#

The angular momentum is

#L=Iomega=61.25*38pi=7312.1kgm^2s^-1#