How Do You Calculate the MOI for a Rod with a Mass Attached?

[user_name12]

Sorry about the somewhat extreme thread but I'm sort of desperate. I missed nearly the whole rotation unit cause of illness and I need to find the MOI for a lab that's due tomorrow. I'm confused about what to plug in where. The lab goal is to find the MOI of a rod of uniform density swinging with a point of rotation at the end of the rod. The rod has a mass attached about 3/4 the way down the rod from the point of rotation. The mass is a circular washer and is about 20 g in weight. The rod is 1 m long and weights 97.1 g. How do you find the MOI of the rod/mass complex

Thanks!

 

[berkeman]

Sorry about the somewhat extreme thread but I'm sort of desperate. I missed nearly the whole rotation unit cause of illness and I need to find the MOI for a lab that's due tomorrow. I'm confused about what to plug in where. The lab goal is to find the MOI of a rod of uniform density swinging with a point of rotation at the end of the rod. The rod has a mass attached about 3/4 the way down the rod from the point of rotation. The mass is a circular washer and is about 20 g in weight. The rod is 1 m long and weights 97.1 g. How do you find the MOI of the rod/mass complex

Thanks!

Welcome to the PF. Hope you're feeling better.

This resource should help you out:

http://en.wikipedia.org/wiki/Moment_of_inertia

.