# Moment of inertia

#### ViewtifulBeau

A uniform thin rod has a length 3.14 m and mass 2.11 kg. Find the moment of inertia in kg-m2 about an axis that is perpendicular to the rod and passes through the rod at a distance of 0.67 m from the end of the rod.

I know that if the axis was in the center of the rod the equation would be 1/12 * M *L^2 . M =mass L = length.

I don't know what to do with the axis being in a different place. is it the same eqation(doubt it) or the left half minus the right half or what?

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#### Pyrrhus

Homework Helper
Use the Parallel axis or Steiner's Theorem.

#### whozum

Have you heard of the Parallel Axis Theorem?

#### Tide

Homework Helper
Did you learn about the parallel axis theorem?

hahahahaha

#### Tide

Homework Helper
ECHO, Echo, echo!! ;)

#### ViewtifulBeau

well thanks for the quick relpies, ummm yeah here in my book it is I = I(cm) +Mh^2

is I(cm) = 1/12 * M *L^2?
M is total mass
and h would be..... distance from the center of mass?

#### whozum

This is true.

"Moment of inertia"

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