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A recurrence relation is an equation that recursively defines a sequence, once one or more initial terms are given: each further term of the sequence is ... more

The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume. The density of a material varies with temperature ... more

In optics, the numerical aperture (NA) of an optical system is a dimensionless number that characterizes the range of angles over which the system can ... more

The Prandtl number (Pr) or Prandtl group is a dimensionless number, named after the German physicist Ludwig Prandtl, defined as the ratio of momentum ... more

Thrust is a reaction force described quantitatively by Newton’s second and third laws.

The power needed to generate thrust and the force of the
... more

In physics, the gyromagnetic ratio (also sometimes known as the magnetogyric ratio in other disciplines) of a particle or system is the ratio of its ... more

Ellipse is a curve on a plane surrounding two focal points such that a straight line drawn from one of the focal points to any point on the curve and then ... more

Sensible heat is heat exchanged by a body or thermodynamic system that changes the temperature, and some macroscopic variables of the body, but leaves ... more

A magnetic dipole is a closed circulation of electric current. A simple example of this is a single loop of wire with some constant current through ... more

In a fluid at rest, all frictional stresses vanish and the state of stress of the system is called hydrostatic.For water and other liquids, this integral ... more

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