What is the moment of inertia of a pendulum with a mass of #5 kg# that is #9 m# from the pivot?

1 Answer
Jan 2, 2016

Answer:

#I=r^2*m=9^2*5 kg*m^2 = 405 kg*m^2#

Explanation:

The moment of inertia is defined as the distances of all infinitely small masses distributed across the body's whole mass. As an integral:

#I=intr^2dm#

This is useful for bodies of which geometry can be expressed as a function. However, since you only have one body in a very specific spot, it is simply:

#I=r^2*m=9^2*5 kg*m^2 = 405 kg*m^2#