Реферат: Физические законы, переменные, принципы

The pressure law. The pressure of an ideal gas is directly proportional to the thermodynamic temperature at constant volume.

Joule-Thomson effect; Joule-Kelvin effect (J. Joule, W. Thomson)

The change in temperature that occurs when a gas expands into aregion of lower pressure.

Joule's laws

Joule's first law. The heat produced when an electric current flows through a resistance for a specified time is equal to the square of the current multiplied by the resistivity multiplied by the time.

Joule's second law. The internal energy of an ideal gas is independent of its volume and pressure, depending only on its temperature.

Josephson effects (B.D. Josephson; 1962)

Electrical effects observed when two superconducting materials areseparated by a thin layer of insulating material.

Kepler's laws (J. Kepler)

Kepler's first law . A planet orbits the Sun in an ellipse with the Sun at one focus.

Kepler's second law . A ray directed from the Sun to a planet sweeps out equal areas in equal times.

Kepler's third law . The square of the period of a planet's orbit is proportional to the cube of that planet's semimajor axis; the constant of proportionality is the same for all planets.

Kerr effect (J. Kerr; 1875)

The ability of certain substances to differently refract lightwaves whose vibrations are in different directions when thesubstance is placed in an electric field.

Kirchhoff's law of radiation (G.R. Kirchhoff)

The emissivity of a body is equal to its absorptance at the sametemperature.

Kirchhoff's rules (G.R. Kirchhoff)

The loop rule. The sum of the potential differences encountered in a round trip around any closed loop in a circuit is zero.

The point rule. The sum of the currents toward a branch point is equal to the sum of the currents away from the same branch point.

Kohlrausch's law (F. Kohlrausch)

If a salt is dissolved in water, the conductivity of the solutionis the sum of two values -- one depending on the positive ions andthe other on the negative ions.

Lambert's laws (J.H. Lambert)

Lambert's first law. The illuminance on a surface illuminated by light falling on it perpendicularly from a point source is proportional to the inverse square of the distance between the surface and the source.

Lambert's second law. If the rays meet the surface at an angle, then the illuminance is also proportional to the cosine of the angle with the normal.

Lambert's third law. The luminous intensity of light decreases exponentially with the distance that it travels through an absorbing medium.

Landauer's principle

A principle which states that it doesn't explicitly take energy tocompute data, but rather it takes energy to erase any data,since erasure is an important step in computation.