Using the concepts of quanta and photons, explain the difference between a 100-W

Question

Using the concepts of quanta and photons, explain the difference between a 100-W and 40-W light bulb if they both produce only green light. Post your answers in the discussion area for the following questions: Why does the 100-W bulb appear brighter than the 40-W bulb? Why would you expect the 100-W bulb to feel hotter than the 40-W bulb? If 10% of the energy consumed by the bulb produces green light of 500 nm, how many green photons does each bulb produce each second? How does this support your explanation of brightness?

Explanation / Answer

According to the given problem,

a)
the number of emitted photons/time of 100 W is > than 40 W light bulb

b)
the intensity then the energy flow of 100 W is > than 40 W light bulb
the absorbed energy transformed in heat of 100 W light bulb is > than 40 W light bulb

c)
W = n h c /
then
n1 = 100 / (h c) = 2.5x10^20 photons/second [100 W]
n2 = 40 / (h c) = 1x10^20 photons/second [40 W]

d)
Above brightness is confirmed using the Answer a

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