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

Explain isolated system, ISOLATED SYSTEM: "When a number of bodies are ...

ISOLATED SYSTEM: "When a number of bodies are like that they can exert force upon one another and no external agency exerts a force on them, they are said to form an isolated s

Electrons in silicon, At 200.0 K, silicon has 3.79 x 10 -18 free electrons...

At 200.0 K, silicon has 3.79 x 10 -18 free electrons per atom. How many free electrons/cm 3 are there in silicon at this temperature?

Gravity.., what is quantum gravity

what is quantum gravity

Grammer usage mechanics, Which word in the sentence is the participle? A...

Which word in the sentence is the participle? Around the year 1500, Leonardo da Vinci, a great inventor and painter, designed plans for a flying machine, but it was never built.

Construction and working of nicol prism, Briefly explain with principle, th...

Briefly explain with principle, the construction and working of Nicol prism. Why the angle of incidence on Nicol prism would be around 14 o .

What is the cheetah average acceleration, A cheetah can reach a top speed o...

A cheetah can reach a top speed of 27.8 m/s in 5.2 s. What is the cheetah's average acceleration?

How fast must a spacecraft travel relative to the earth, How fast must a sp...

How fast must a spacecraft travel relative to the earth for each day on the spacecraft to correspond to 2d on the earth? By standard equation, for the time t to the earth to co

What do you mean by a shunt, What do you mean by a shunt? Reduce expression...

What do you mean by a shunt? Reduce expressions for the current flowing through the shunt resistance and galvanometer. Describe the principle on which a transformer works. Defin

What is the difference between unit cell and primitive cell, What is the di...

What is the difference between unit cell and primitive cell In primitive cell, number of atoms per unit cell is one while if number of atoms per unit cell is greater than one i

What is its potential energy in joules, Assume a crane lifts a 900 kilogram...

Assume a crane lifts a 900 kilogram wrecking ball 12 meters above a concrete slab.  105,840 Joules of potential energy are kept in the wrecking ball.  Now the ball is dropp

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