--%>

Define Constancy principle

Constancy principle (A. Einstein): One of the postulates of Sir Einstein's special theory of relativity that puts forth that the speed of light in vacuum is computed as similar speed to all observers, in spite of of their relative motion. That is, if I'm travelling at 0.9 c away from you, and fire a beam of light in that direction, both you and I will separately compute the speed of that beam as c.

One of the outcomes of this postulate (i.e., one of the predictions of the special relativity) is that no massive particle can be accelerated to (or beyond) the light speed, and therefore the speed of light also symbolizes the eventual cosmic speed limit. Only mass-less particles (collectively termed as luxons, comprising photons, gravitons, and probably neutrinos, must they prove to indeed be mass-less) travel at light speed, and all other particles should travel at slower speeds.

   Related Questions in Physics

  • Q : What is Farad or SI unit of capacitance

    What is Farad or SI unit of capacitance? Farad: F (after M. Faraday, 1791-1867): The derived SI unit of the capacitance stated as the capacitance in a capacitor that, when charged to 1 C, contains

  • Q : Explain avogadro's hypothesis

    Avogadro's hypothesis (Count A. Avogadro; 1811): Equivalent volumes of all gases at similar temperature and pressure contain equivalent numbers of molecules. This is, in fact, true only for the ideal gases.  <

  • Q : Define Watt or SI unit of power Watt: W

    Watt: W (after J. Watt, 1736-1819): The derived SI unit of power, stated as a power of 1 J acting over the period of 1 s; it therefore has the units of J/s.

  • Q : Define Tipler machine Tipler machine:

    Tipler machine: The solution to Einstein's equations of general relativity which permits time travel. A tremendously dense (that is, on the order of the density of neutron star matter), infinitely-long cylinder that rotates very quickly can form close

  • Q : Define Hall Effect Hall Effect:

    Hall Effect: Whenever charged particles flow via a tube that has both an electric field and a magnetic field (that is perpendicular to the electric field) present in it, only assured velocities of the charged particles are favored, and will make it un

  • Q : Explain Event horizon Event horizon:

    Event horizon: The radius which a spherical mass should be compressed to in order to convert it into a black hole, or the radius at which the time and space switch responsibilities. Once within the event horizon, it is basically impossible to escape t

  • Q : Explain Photoelectric effect

    Photoelectric effect: An effect described by A. Einstein that demonstrates that light seems to be made up of particles, or photons. The light can excite electrons (termed as photoelectrons in this context) to be ejected from the metal. Light with a fr

  • Q : Define Rayleigh criterion or resolving

    Rayleigh criterion: resolving power: The criterion for determining how delicately a set of optics might be able to differentiate. This  starts with the supposition that central ring of one image must fall on the first dark ring of the other; for

  • Q : Explain Davisson-Germer experiment

    Davisson-Germer experiment (C.J. Davisson, L.H. Germer; 1927): The experiment which conclusively proved the wave nature of electrons; diffraction patterns were examined by an electron beam penetrating into the nickel target.

  • Q : Define Systeme Internationale d'Unites

    Systeme Internationale d'Unites (SI): The rationalized and coherent system of units derived from the m.k.s. system (that itself is derived from metric system) in common utilization in physics nowadays.