Flywheel

Definition

A flywheel is a rotating mechanical device designed to store rotational energy. It helps maintain a constant angular velocity by resisting changes in rotational speed due to its high moment of inertia.

5 Must Know Facts For Your Next Test

1. The moment of inertia of a flywheel depends on its mass distribution relative to the rotation axis.
2. Flywheels are used to smooth out fluctuations in mechanical systems, such as engines and power plants.
3. The rotational kinetic energy of a flywheel is given by the formula $K = \frac{1}{2}I\omega^2$, where $I$ is the moment of inertia and $\omega$ is the angular velocity.
4. Flywheels can be used to temporarily store energy during regenerative braking in vehicles.
5. High-speed flywheels are often made from composite materials like carbon fiber for higher strength-to-weight ratios.

Review Questions

• What factors determine the moment of inertia of a flywheel?
• How does a flywheel help in maintaining constant angular velocity in mechanical systems?
• Write and explain the formula for calculating the rotational kinetic energy of a flywheel.

Related terms

Moment of Inertia: A measure of an object's resistance to changes in its rotation rate, dependent on mass distribution relative to the axis of rotation.

Rotational Kinetic Energy: The energy possessed by a rotating object, calculated using $K = \frac{1}{2}I\omega^2$.

Angular Velocity: The rate at which an object rotates or revolves around an axis, measured in radians per second ($\omega$).