(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I want to calculate the moment of inertia of a 2d triangle. Let's say we've got a triangle with sides of 20 units. So it has width 20 and height 17,32.

Also, let's say this triangle has a mass of 173.20 mass units (just used the surface). Now I want to calculate the moment of inertia from a given axis of rotation.

2. Relevant equations

I = M*r^2 for point mass

3. The attempt at a solution

Since the triangle is basically built from an infinite number of point masses, but it has no use to divide the mass by the number of point masses, and calculate the MI for every single point. There must be a more easy way of calculating the moment of inertia for basic geometric shapes, with a given axis of rotation. But I can only find the theory of shapes being built from point masses. Please help

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Rigid body moment of inertia

**Physics Forums | Science Articles, Homework Help, Discussion**