Created By : Vaibhavi Kumari

Reviewed By : Rajashekhar Valipishetty

Last Updated : May 17, 2023

The Rotational Kinetic Energy Calculator is a free, portable calculator that calculates rotational kinetic energy using inputs such as angular velocity, the moment of inertia, and other variables. Get step-by-step instructions on how to calculate rotational kinetic energy, including formulas, units, and more.

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Angular velocity:
Moment of inertia:

What is Rotational Kinetic Energy?

Kinetic energy includes rotational energy. It describes the energy of a moving object. While conventional kinetic energy was associated with items moving in a straight line, rotational energy is associated with spinning objects. As a result, instead of using a constant speed in our computations, we must employ angular velocity.

Remember that an object has both regular and rotational kinetic energy while it is in translation (going in a straight line) and rotation (turning around its axis). As a result, to determine its total energy, you must compute both numbers and add them together.

Rotational Kinetic Energy Formula

We may describe Rotational Kinetic Energy with a simple yet clear formula, just like any other form of energy. RE = 1/2 * I * ω²

  • RE = The rotational kinetic energy is measured in Joules.
  • I = The moment of inertia is measured in kilograms per square metre, and its units are kilograms per square metre.
  • ω = It is the angular velocity, which is measured in Hertz (Hz) or Revolutions Per Second (RPS) (RPM)

For more concepts check out to get quick answers by using the free tools available.


How to Calculate Rotational Kinetic Energy?

Learn how to calculate Rotational Kinetic Energy by following the easy procedure described below. As so, they are.

  • Step 1: To begin, determine the wheel's angular velocity.
  • Step 2: Determine the wheel's Moment of Inertia later.
  • Step 3: Once you have these two values, plug them into the rotational kinetic energy formula to determine the wheel's rotational kinetic energy.

Rotational Kinetic Energy Examples

Question 1:A round grindstone with a moment of inertia 1800 kg.m² is rotating at an angular velocity of 7.5 radians per sec. What is the rotational kinetic energy of a grindstone?



Moment of Inertia = 1800 kg.m²

Angular Velocity = 7.5 Rad/Sec

Rotational Kinetic Energy = 1/2 * I * ω²

RE = 1/2*1800*7.5²

RE = 50,625 J


FAQs on Rotational Kinetic Energy

1. How to find out the Rotational Kinetic Energy?

Determine the angular velocity and moment of inertia of the wheel first. Then, quickly calculate Rotational Kinetic Energy by plugging them into the rotational kinetic energy formula.

2. What is the Earth's rotational kinetic energy as it orbits the sun?

We now know that the earth takes 365 days to orbit the sun. In its orbit around the Sun, the Earth's rotational kinetic energy is 2.67 1033 J.

3. What is the formula for calculating rotational inertia?

According to the formula rotational inertia = mass x radius^2, rotational inertia is a scalar, not a vector, and is dependent on the radius of rotation. The measure of an object's resistance to change in its rotation is called rotational inertia.

4. What is the Rotational Kinetic Energy Formula?

RE = 1/2 I ω² is the formula for Rotational Kinetic Energy.

5. What is Rotational Kinetic Energy?

Rotational Kinetic Energy is a type of kinetic energy that is created when an item rotates. It is a component of total kinetic energy.

6. How do you compute the earth's rotational kinetic energy?

The rotational kinetic energy of the Earth's rotation about its axis at its core is one-half of the sphere's moment of inertia, which is two times the Earth's mass times its radius squared divided by five, and then multiplied by the Earth's angular velocity squared.