--%>
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 : Collision & Transition State Theory

    Assuming ideal gas: a)  Calculate the average velocity of a nitrogen molecule at 298K and compare to the velocity of a helium molecule at the same conditions. b)      Calculate the temperature wh

    		•
  • Q : Explain Chronology protection conjecture

    Chronology protection conjecture (S.W. Hawking): The notion that the formation of any closed time like curve will (automatically) involuntarily be destroyed by the quantum fluctuations as soon as it is made. In another words, the quan

    		•
  • Q : Biot-Savart law Biot-Savart law (J.B.

    Biot-Savart law (J.B. Biot, F. Savart) - The law which explains the contributions to the magnetic field by an electric current. This is analogous to the Coulomb's law. Mathematically: dB = (mu0 I)/(4 pi r2) dl cross e

    		•
  • Q : Describe the term Specular Reflection

    Describe briefly the term Specular Reflection?

    		•
  • Q : Calculate the intensity I along y axis

    As shown in the figure below, a source at S is sending out a spherical wave: E1=(A×D/r) cos(wt-2πr/λ); where r is the distance to source

    		•
  • Q : Continuity of equation or Equation of

    Define Equation of continuity or Continuity of equation: An equation that states that a fluid flowing via a pipe flows at a rate that is inversely proportional to the cross-sectional region of the pipe. That is, when the pipe constric

    		•
  • Q : Free fall acceleration What do you mean

    What do you mean by the term free fall acceleration? State its significance in brief?

    		•
  • Q : Problem on two coupled coils connected

    In a series adding connection, two coupled coils have equivalent inductances LA; in a series opposing connection, LB. Determine an expression for M in terms of LA and LB. What does the outcome suggest?

    		•
  • Q : Report on Radiobiology for Travel Space

    I have a problem in wirting a report on Radiobiology for Travel Space.  Can someone provide me a complete report on the above topic.

    		•
  • Q : Explain Ohms law Ohm's law (G. Ohm;

    Ohm's law (G. Ohm; 1827): The ratio of the potential difference among the ends of a conductor to the current flowing via it is constant; the constant of proportionality is termed as the resistance, and is distinct for different materials.

    		•