The missing question is: how many photons are produced per second?
Answer:
Explanation:
The energy of a photon is given by
where
h is the Planck constant
c is the speed of light
is the wavelength of the photon
In this problem, the photons have wavelength
, so each photon has an energy of
The total energy emitted by the bulb in 1 second is
E = 100 J
Therefore, the number of photons emitted per second is