Population inversion and luminous flux, Physics

Assignment Help:

POPULATION INVERSION and LUMINOUS FLUX:

POPULATION INVERSION: The process in which number of electrons (N ) in a higher2 energy state called metastable state of an active medium is increased to a value greater than the number (N ) in the ground state (i.e. N  > N ) is called population inversion.

LUMINOUS FLUX : The amount of radiant (light) energy following from a source of light per unit time is called luminous flux or light flux (Φ) . It is measured in lumens.

LUMINOUS INTENSITY : Luminous intensity of a point source of light is defined as the luminous flux emitted from it per unit solid angle.

It is otherwise called Illuminating power (I). It is measured in candela (cd).

 

 


Related Discussions:- Population inversion and luminous flux

Find average distance of an electron in an atom, The average distance of an...

The average distance of an electron in an atom from its nucleus is of the order of: (1) 10 6 m (2) 10 -6 m (3) 10 -10 m (4)10 -15 m Ans: (3) 10 -10 m

Determine the vertical reaction, The boom DF and the column DE have a unifo...

The boom DF and the column DE have a uniform weight of P55 N/m and the chain and load at F is P56 kN.  Determine the Shear Force in kN rounded to 1 DP and the Bending Moment in kN.

Electrical Charge, if 36C of charge pass through a wire in 4 seconds what c...

if 36C of charge pass through a wire in 4 seconds what current is it carrying

Determine the magnitude of the force in direct current, The weightless trus...

The weightless truss shown below supports loads at point A & B and is fastened to the supports at C & E.  The value of F1 in kN is given in P13 and the value of F2 in kN is given i

Superfluidity, Superfluidity: The phenomena through which, at sufficie...

Superfluidity: The phenomena through which, at sufficiently low temperatures, a fluid can flow along zero viscosity. Its causes are related with superconductivity.

Draw the final image formed by two lenses, Draw the final image formed by t...

Draw the final image formed by two lenses: An optical imaging system consists of two positive lenses (L1 and L2). L1 has a focal length f 1 = 10 cm, and L2 has a focal length

Evolution of hydrogen , A strip of aluminium of mass 40.7g is dropped into ...

A strip of aluminium of mass 40.7g is dropped into a beaker of dilute hydrochloric acid. Calculate the work done (in J) on the surrounding atmosphere (1atm pressure, 26.1 o C ) by

Explain the magnetize of metal, Q. Explain the magnetize of metal? Ans...

Q. Explain the magnetize of metal? Answer:- You can rub a magnet alongside the metal in one direction for a bunch of times (the more the better) and that will magnetize it

What is physical quantity, A quantity that can be calculated by instrument,...

A quantity that can be calculated by instrument, clearly defined and has proper units is known as physical value. Physical quantities are described as fundamental and derived quant

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd