What is the angular momentum of an object with a mass of #5 kg# that moves along a circular path of radius #4 m# at a frequency of # 4 Hz #?

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1 Answer
Sep 9, 2016

I'll illustrate it below.

Explanation:

The mass of the object is #m = 5 kg# and radius of the path is #r = 4 m#.

Now, frequency is #f = 4 Hz#
But, we know that, angular frequency #omega = 2pif#

Thus, #omega = 8pi# #radian# #s^-1#

Now, we have the relation from elementary dynamics that,

#L = Iomega# where #I# is the magnitude of the moment of inertia about the concerned axis.
Further, #I = mr^2# which implies that #L = momegar^2#

We have now deduced an expression for the angular momentum #L# in terms of mass #m#, angular velocity #omega# and radius of path #r#.

All you have to do now is plug in the values and get the final result. I won't be doing it for you though.
I'm leaving it as an exercise.

I hope it helped.