Home
Class 12
PHYSICS
A monochromatic source of light operatin...

A monochromatic source of light operating at 200W
emits `4 xx (10^20)` photons per second. Find the wavelength
of the light.

Text Solution

Verified by Experts

The energy of each photon = `(200 J(s^-1)/ 4 xx (10^20)(s^-1))`
`= 5 xx (10^-19)J. `
`Wavelength= lambda= hc/E `
` = ((6.63 xx (10^-34)J s) xx (3 xx (10^8)m(s^-1))/ ( 5 xx (10^-19)J)) `
` = 4.0 xx (10^-7)m= 400 n m. `
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • PHOTO ELECTRIC EFFECT AND WAVE PARTICLE DUALITY

    HC VERMA|Exercise Short Answer|13 Videos

  • PHOTO ELECTRIC EFFECT AND WAVE PARTICLE DUALITY

    HC VERMA|Exercise Objective 1|14 Videos

  • PHOTO ELECTRIC EFFECT AND WAVE PARTICLE DUALITY

    HC VERMA|Exercise Worked Out Examples|2 Videos

  • PERMANENT MAGNETS

    HC VERMA|Exercise Exercises|25 Videos

  • PHOTOMETRY

    HC VERMA|Exercise Exercises|16 Videos

Similar Questions

Explore conceptually related problems

A monochromatic source of light operation at 200 W emits 4xx10^(20) photons per second. Find the wavelength of the light "(in" 10^(-7)m ).

A monochromatic source of light operating at 200W emits 4*10^(20) photons per second.Find the wavelength of the light nearly

Knowledge Check

  • A 20 W light source emits monochromatic light of wavelength 600 nm the number of photons ejected per second in the form of avogardro 's number will be

    A
    `N_(A)`
    B
    `10^(-2)N_(A)`
    C
    `10^(-4)N_(A)`
    D
    `10^(-6)N_(A)`

    • Similar Questions

    Explore conceptually related problems

    A monochromatic source of light operating at 500W emits 6xx10^(20) photon per second. Find the wavelength of the light used. Use h=6.6xx10^(-34)Js , C=3xx10^8m//s

    A monochromatic source of light operating at 200W emits 4xx10^(-20) photons/sec. Find the wavelength of the light . (Given h = 6.63xx10^(-34) Js)

    If a monochromatic source of light of power 1 kW emits 6xx10^(22) photons per second , then what should be the frequency of light emitted from the source ?

    A monochromatic light source of intensity 5 m W emits (8x10^15) photons per second . This light ejects photoelectrons from a metal surface. The stopping potential for this setup is 2.0 V. Calculate the work function of the metal.

    What is power (in watt) of a light source emitting 3.125 xx 10^(18) photons per second, while the wavelength of light is 620 nm ? (use hc = 12400 eVÅ )

    A monochromatic source emits light of wavelength 550 nm is emitted by a source . Find the number of photons emitted by the source in 90 seconds if power of source is 60 W.

    A monochromatic source emits light of wavelength 500 nm and has a power output of 25 W. Find the number of photons emitted by this source in 5 minutes .

    Home
    Profile