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The radiation pressure force of the light circulating in the cavity can damp or amplify the oscillation of the mirror on the spring. Main articles: Cavity optomechanics and Laser cooling The reflection of a laser pulse from the surface of an elastic solid can give rise to various types of elastic waves that propagate inside the solid or liquid.
The force of attraction or repulsion between two electrically charged particles, in addition to being directly proportional to the product of the electric charges, is inversely proportional to the square of the distance between them; this is known as Coulomb's law. The deviation of the exponent from 2 is less than one part in 10 15. [8]
Intensity can be found by taking the energy density (energy per unit volume) at a point in space and multiplying it by the velocity at which the energy is moving. The resulting vector has the units of power divided by area (i.e., surface power density). The intensity of a wave is proportional to the square of its amplitude.
A point source of light produces spherical wavefronts. The irradiance in this case varies inversely with the square of the distance from the source. = =, where r is the distance; P is the radiant flux; A is the surface area of a sphere of radius r.
Light, or more generally an electromagnetic wave, carries not only energy but also momentum, which is a characteristic property of all objects in translational motion. The existence of this momentum becomes apparent in the "radiation pressure " phenomenon, in which a light beam transfers its momentum to an absorbing or scattering object, generating a mechanical pressure on it in the process.
The Lorentz self-force derived for non-relativistic velocity approximation , is given in SI units by: = ˙ = ˙ = ˙ or in Gaussian units by = ˙. where is the force, ˙ is the derivative of acceleration, or the third derivative of displacement, also called jerk, μ 0 is the magnetic constant, ε 0 is the electric constant, c is the speed of light in free space, and q is the electric charge of ...
The shape of a Gaussian beam of a given wavelength λ is governed solely by one parameter, the beam waist w 0. This is a measure of the beam size at the point of its focus (z = 0 in the above equations) where the beam width w(z) (as defined above) is the smallest (and likewise where the intensity on-axis (r = 0) is the largest). From this ...
There are two factors that determine the degree to which a medium containing particles will attenuate a light beam: the number of particles encountered by the light beam, and the degree to which each particle extinguishes the light. [15] Assume that a beam of light enters a material sample. Define z as an axis parallel to the direction of the ...