A modern 200 W sodium street lamp emits yellow light of wavelength 0.6 `mum`. Assuming it to be 25% efficient in converting electrical energy to light, the number of photons of tellow light it emits per second is

A 200 W sodium street lamp emits yellow light of wavelength 0.6 μm. Assuming it to be 25% efficient in converting electrical energy to light, the number of photons of yellow light it emits per second is

A 200W sodium street lamp emits yellow ligth of wave length 0.6 mum . Assuming it to be 25% efficient in converting electrical energy to light the number of photons of yellow ligth it emits per second is a

A 150 W lamp emits light of mean wavelength of 5500Å . If the efficiency is 12% , find out the number of photons emitted by the lamp in one second.

A special kind of light bulb emits monochromatic light of wavelength 630 nm. Electrical energy is supplied to it at the rate of 60 W, and the bulb is 93% efficient at converting that energy to light energy. How many photons are emitted by the bulb during its lifetime of 730 h?