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

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 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 100 watt buble emits monochromatic light of wavelength 400 nm. Then the number of photons emitted per seccond by the buble is nearly -

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 .

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