A 100 watt bulb emits monochromatic light of wavelength 400 nm Calculate the number of photons emitted per second - Chemistry - Structure of Atom

Question

A 100 watt bulb emits monochromatic light of wavelength 400 nm
Calculate
the number of photons emitted per second by the bulb

Shaheen A. Salam · Accepted Answer

Given,
Power of the bulb = 100 watt = work/time = 100 J/s
Energy of one proton,         E = hcλh = 6
626×10-34Jsc = 3×108m/sλ = 400×10-9mTherefore,     E= 6
626×10-34Js×3×108m/s400×10-9m                         = 4
969 × 10-19 JNo
 of photos emitted per second                         = 100 J/s4
969×10-19J= 2 012×1020 s-1

12
E=hcλor, λ=hcEE= 1eV = 1
60×10-19 JTherefore, E=6
626×10-34×3×1081 60×10-19=12
42×10-7 m= 0 0124×10-10 m = 0
0124 A°

A 100 watt bulb emits monochromatic light of wavelength 400 nm. Calculatethe number of photons emitted per second by the bulb.

A 100 watt bulb emits monochromatic light of wavelength 400 nm. Calculate
the number of photons emitted per second by the bulb.