Wiktionary
n. (context physics English) The kinetic energy of a rotating rigid body otherwise at rest
Wikipedia
Rotational energy or angular kinetic energy is kinetic energy due to the rotation of an object and is part of its total kinetic energy. Looking at rotational energy separately around an object's axis of rotation, the following dependence on the object's moment of inertia is observed:
$$E_\mathrm{rotational} = \frac{1}{2} I \omega^2$$
where
The mechanical work required for / applied during rotation is the torque times the rotation angle. The instantaneous power of an angularly accelerating body is the torque times the angular velocity. For free-floating (unattached) objects, the axis of rotation is commonly around its center of mass.
Note the close relationship between the result for rotational energy and the energy held by linear (or translational) motion:
$$E_\mathrm{translational} = \frac{1}{2} m v^2$$
In the rotating system, the moment of inertia, I, takes the role of the mass, m, and the angular velocity, ω, takes the role of the linear velocity, v. The rotational energy of a rolling cylinder varies from one half of the translational energy (if it is massive) to the same as the translational energy (if it is hollow).
An example is the calculation of the rotational kinetic energy of the Earth. As the Earth has a period of about 23.93 hours, it has an angular velocity of 7.29×10 rad/s. The Earth has a moment of inertia, I = 8.04×10 kg·m. Therefore, it has a rotational kinetic energy of 2.138×10 J.
Part of it can be tapped using tidal power. Additional friction of the two global tidal waves creates energy in a physical manner, infinitesimally slowing down Earth's angular velocity ω. Due to the conservation of angular momentum, this process transfers angular momentum to the Moon's orbital motion, increasing its distance from Earth and its orbital period (see tidal locking for a more detailed explanation of this process).
Usage examples of "rotational energy".
If it's a kernel, a Kerr-Newman black hole, it also has rotational energy and a magnetic moment.
The energy we extract comes from the rotational energy of the spinning black hole, and if a hole is not spinning, no energy can possibly be extracted from it in this way.
When two stars condensed together out of a single gas cloud they seemed to take care of each other's excess rotational energy.
The total rotational energy of the Earth is only one-thousandth of the planet's gravitational self-energy, but that is still an incredibly big number.
It flexed the Earth s crust continually as the Earth rotated and it slowed the Earth s rotation, both through that flexing and through the friction of the ocean s water tides on shallow sea bottoms--so that rotational energy was converted to heat.
It flexed the Earth's crust continually as the Earth rotated and it slowed the Earth's rotation, both through that flexing and through the friction of the ocean's water tides on shallow sea bottoms-so that rotational energy was converted to heat.
We pick up some of the rotational energy of the galactic core itself when we whip around it.
The shells rotational energy, converted by breaking into heat, had raised its temperature to a point where its radiation could be picked up by the ships meters.
The shell's rotational energy, converted by breaking into heat, had raised its temperature to a point where its radiation could be picked up by the ship's meters.
Plenty of capacity to take up the rotational energy of the pod if it had any, slow down the impact to something that MacArthur might be able to handle.