A 110-W arc lamp operates with an effiency of 6% for emitting light. it emits light of wavelength 585 nm. How many photons per second does it emit?
a) 3.2 * 10^20
b) 3.2 * 10 ^9
c) 4.0 * 10 ^18
d) 1.2 * 10^19
e) 1.9 * 10^19
a) 3.2 * 10^20
b) 3.2 * 10 ^9
c) 4.0 * 10 ^18
d) 1.2 * 10^19
e) 1.9 * 10^19
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Energy of each photon: hc/wavelength = 3.34*10^-19J
Energy emitted by lamp as photons: 110 * 0.06 = 6.6 J/s
Then just divide 6.6 by 3.34*10^-19 to get the number of photons emitted per second.
answer is e, 1.9*10^19 photons per second.
Energy emitted by lamp as photons: 110 * 0.06 = 6.6 J/s
Then just divide 6.6 by 3.34*10^-19 to get the number of photons emitted per second.
answer is e, 1.9*10^19 photons per second.