The Rotational energy, also known as angular kinetic energy is the kinetic energy produced because of the rotation of an object or an entity and is a fraction of its total kinetic energy. Rotational energy occurs when any form of matter rotates around a center of rotation. Rotational energy can be transformed into other forms of energy, particularly heat and translational (linear) energy. According to the law of conservation of energy, eventually, the total amount of energy in a remote system must stay constant. Loss in energy of one type must result in the gain in energy of another type. Energy transfer between the types mostly takes place through the swap over of momentum between the atomic particles of matter. Besides rotational energy, some other examples of various forms of energy consist of chemical, potential, and thermal. Hence, rotational energy is one of numerous potential ways that matter can take hold of energy.
Examining rotational energy individually around the axis of rotation of object, the reliance of rotational energy on the moment of inertia of the object is given by the relationship: Erotational = 1/2 I ω ^ 2, where, ω is the angular speed, I is the moment of inertia around the axis of rotation and E is the kinetic energy. The mechanical work needed for or which is applied throughout rotation is the torque (a twisting force) times the rotation angle. The immediate power of an angularly accelerating body is the torque or twisting force times the angular frequency. In case of the free-floating or unattached entities or objects, the axis of rotation is usually in the region of its center of mass.
The relationship between the linear (or translational) and rotational motion is given as: E translational = 1/2 mv ^2, where, m is the mass and v is the linear velocity. It should be noted that in the rotating system, the moment of inertia, I takes the function of the mass, m, and the angular velocity, ω, takes the function of the linear velocity, v. The rotational energy of a rotating cylinder or any rotating object differs from one half of the translational energy (in case of massive) to the same as the translational energy (in case of hollow).
There are number of similarities between rotational energy and linear kinetic energy.
A Flywheel battery is a best realistic application of rotational energy. A flywheel battery stocks up rotational energy, similar to how a standard battery stocks up the electrical energy. In a train using flywheel battery, the linear kinetic energy of the moving train can be shifted to the rotational energy of the aboard flywheel. The effect of this shift will be a decrease in the velocity of the train. If there is no energy loss as heat, all the energy of the train’s movement can be stored in the flywheel and utilized after a while for speeding up the train.