Created By : Naaz Fatima

Reviewed By : Phani Ponnapalli

Last Updated : Apr 10, 2023

Mass Moment of Interia Calculator is an instant online tool that finds the moment of interia of objects of various shapes by just entering the details in the input fields. Press on the calculate button after providing the mass, distance and get the results in a less amount of time.

Step by Step Process to Find Moment of Interia

The detailed steps to calculate the mass moment of interia for different shapes are given below. Follow these guidelines and instructions to get the value easily.

  • Make a note of the given details in the question.
  • Get the formula and substitute the values in the formula
  • Perform the required math operations to find the moment of interia value.

Moment of Interia Formulas

Moment of Interia is also known as the angular mass of the object. Mass moment of interia is defined as the tendency of an object to maintain the state of rest or motion. The body movement is calculated using the moment of interia.

The SI unit of moment of interia is kilogram meter square.

The following are the moment of interia formulas for different shapes.

  • Moment of Interia of a ball I = (2/5)mr┬▓
  • Moment of Interia of circular hoop I = mr┬▓
  • Cuboid Moment of Interia I = (1/12) m(w┬▓ + h┬▓) or (1/12)m(l┬▓ + h┬▓) or (1/12)m(l┬▓ + w┬▓)
  • Moment of Interia of Cylinder I = (1/2)mr┬▓ or (1/12)m(3r┬▓ + h┬▓)
  • Cylindrical shell moment of interia I = mr┬▓
  • Moment of Interia of Cylindrical tube I = (1/2)m(rΓéé┬▓ + rΓéü┬▓) or (1/12)m(3(rΓéé┬▓ + rΓéü┬▓) + h┬▓)
  • >Disk moment of interia I = (1/2)mr┬▓ or (1/4)mr┬▓
  • Isosceles Trinagle Moment of Interia I = (1/2)mL┬▓(1 - (2/3)sin┬▓(╬▓))
  • Moment of Interia Octahedron I - (1/10)ms┬▓
  • Point of mass moment of interia I = mr┬▓
  • Rectangular plate moment of interia I = (1/12)m(w┬▓ + l┬▓)
  • Moment of interia of sphere I = (2/3)mr┬▓
  • Two point masses moment of interia I = (mΓéümΓéé)r┬▓/(mΓéü + mΓéé)


Question: A object of mass 5 kg is situated at a distance of 15 m from the axis of rotation. Find the moment of interia about the axis of rotation.


Given that

Mass of the object m = 5 kg

Distance of the object from the axis of rotation d = 15 m

Moment of interia formula is I = md┬▓

I = 5 * 15┬▓ = 5 * 225

= 1125

Thefore, object moment of interia is 1125 kgm┬▓

FAQ's on Mass Moment of Interia Calculator

1. What is the most commonly used moment of interia equation?

The moment of intertia equation is I = mr┬▓. Here m is the mass of the object and r is the distance from the axis of rotation.

2. What are the units of moment of interia?

The SI unit of MOI is kg * m┬▓ and the imperial units is ft * s┬▓ or lb * ft┬▓.

3. Which website is best for finding moment of interia?

Physicscalc.Com is a genuine site where you can calculate the moment of interia for different shaped objects to make all your calculations easier.

4. Calculate the moment of interia of thin rectangular rod having mass 2 kg and length 2 m around the perpendicular bisector and perpendicular axis through one end?

Given that,

Mass m = 2 kg, Lemgth L = 2 m

Moment of interia around the perpendicualr bisector Ip = (mL┬▓)/12

= (2 * 2┬▓)/12 = 2/3 kgm┬▓

Moment of interia about perpendicular axis Ie = (2 * 2┬▓)/3 = 8/3 kgm┬▓