--%>
Assignment Help - homework help

Define Lumen or SI unit of luminous flux

Lumen: lm: The derived SI unit of luminous flux, stated as the luminous flux produced by a uniform point source of 1 cd releasing its luminous energy over a solid angle of 1 sr; it therefore has units of cd sr.

   Related Questions in Physics

  • Q : Define Joule or SI unit of energy Joule

    Joule: J (after J.P. Joule, 1818-1889): The derived SI unit of energy stated as the quantity of work done by moving an object via a distance of 1 m by exerting a force of 1 N; it therefore has units of N m.

    		•
  • Q : Blackbody radiation What is Blackbody

    What is Blackbody radiation - The radiation - that is the radiance at specific frequencies all across the spectrum -- generated by a blackbody -- which is, a perfect radiator and absorber of the heat. Physicists had complexity exp

    		•
  • Q : Define Pseudoforce Pseudoforce : The

    Pseudoforce: The "force" that arises as an observer is plainly treating an accelerating frame as an inertial one.

    		•
  • Q : What is Wiens displacement law constant

    Wien's displacement law constant, b: It is the constant of Wien displacement law. This has the value of 2.897 756 x 10-3 m K.

    		•
  • Q : Explain Thomson experiment or Kelvin

    Thomson experiment: Kelvin effect (Sir W. Thomson [later Lord Kelvin]): Whenever an electric current flows via a conductor whose ends are maintained at various temperatures, heat is discharged at a rate just about proportional to the

    		•
  • Q : Define Cosmological redshift

    Cosmological redshift: The effect where light emanates from a distant source appears redshifted since of the expansion of the space time itself.

    		•
  • Q : What is Pfund series Pfund series: The

    Pfund series: The series that explains the emission spectrum of hydrogen whenever the electron is jumping to the fifth orbital. Each line is in the infrared part of the spectrum.

    		•
  • Q : Problem on Adiabatic law When air is

    When air is compressed adiabatically the law connecting the absolute temperature T and the pressure P is of the form T = A.Pn where A and N are constants. Show by drawing a suitable linear graph that the experimental dat

    		•
  • Q : Define Schwarzschild radius

    Schwarzschild radius: The radius ‘r’ of the event horizon for a Schwarzschild black hole of mass m is specified by (in geometrized units) r = 2 m. In its conventional units: r = 2 G m/c2

    		•
  • Q : Define Second or SI unit of time

    Second: s: The basic SI unit of time, stated as the period of time equivalent to the duration of 9 192 631 770 periods of the radiation analogous to the transition between the two hyperfine levels of the ground state of cesium-133 atom.

    		•