angular momentum

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angular momentum

The cross product of the ordinary momentum of a particle and its position vector, running from the axis of rotation to the body whose momentum is being determined.

In absence of external forces, the angular momentum (AM) remains constant; therefore, a rotating body tends to maintain the same axis of rotation. When torque is applied to a rotating body, the resulting change in AM results in precession. Momentum involved in the rotation of a body about an axis is conserved, as is ordinary momentum. Atomic nuclei possess an intrinsic AM known as “spin”, which is measured in multiples of Planck’s constant.

an·gu·lar mo·men·tum

(ang'gyŭ-lăr mō-men'tŭm)
The spin of MR active nuclei, which depends on the balance between the number of protons and neutrons in the nucleus.


the 'quantity of motion' of a body or object. A vector quantity. linear momentum the product of mass and velocity. The change in linear momentum is equal to the linear impulse. conservation of linear momentum in the absence of external unbalanced forces, the total linear momentum of colliding bodies or objects will remain constant. Commonly applied to racquet/ball impacts. angular momentum the product of moment of inertia and angular velocity. conservation of angular momentum in the absence of an external moment (torque), the angular momentum of a rotating body will remain constant. Often applied to low-velocity flight (e.g. gymnastics) to explain how a body can increase or decrease angular velocity by manipulating moment of inertia (e.g. by 'tucking'). trading of angular momentum if, in the absence of an external moment (torque), an object or body is rotating about one axis (e.g. somersaulting) and rotation about another axis is introduced (e.g. tilt), the result will be a rotation about a third axis (e.g. twist) due to the vector nature of angular momentum. transfer of angular momentum can occur from one part of a body to another in the absence of an external moment (torque) (e.g. if one part of a body increases angular velocity, another part must decrease to conserve angular momentum).
References in periodicals archive ?
n] gives pure mechanical momentum which is responsible for the orbital angular momentum of a photon.
trsi] is the local angular momentum of segment v about its own transverse axis at the ith time percentile expressed in the external reference system; [I.
Integrating the obtained equation and using the principle of conservation of angular momentum, we can find the main external forces momentum that impede the movement of the motor vehicle
Throughout the paper, we examined the error growth of the global error in the positions and velocities of the bodies, and the relative error in the angular momentum and energy.
Virbhadra, "Energy and angular momentum of charged rotating black holes," General Relativity and Gravitation, vol.
Pressure and wind terms of AAMF plus matter and motion terms of oceanic angular momentum functions (OAMF) from the European Centre for Medium Weather Forecast (eCmWF) ERAinterim analysis model for the atmosphere and oceanic model OMCT driven by the same atmospheric model, prepared at IERS/GFZ center (Thomas et al.
As the orbital angular momentum density involves the Poyting vector, the definition of the Poyting vector is based on the electric and the magnetic fields.
is the axial specific angular momentum that is conserved as a consequence of the axial symmetry.
Early chapters give background on energy and angular momentum in reactions, spin control of chemical reactions, the MIE and its physics, and kinetics of isotope fractionation.
So, the Swiss bespoke watchmaker, Angular Momentum, has unveiled a limited- edition of five timepieces with Mumtaz Mahal and Shah Jahan on the dial.
For example, for the l:wl junction the I:J1 element defines the law of angular momentum, h\ = j\LO\, where h\ is the angular momentum of the first link and j\ is its moment of inertia around the centre of mass.