In a certain experiment, when light of wavelength 570 nm is directed on to the photocell, electrons are emitted at the rate of 6.6 10-13 Coulombs/sec. Assume that each photon that impinges on the photocell emits one electron.
How many photons per second are striking the photocell?
To find the number of photons per second striking the photocell, we can use the equation:
Number of photons per second = Current / Charge per photon
From the given information, we know that the current is 6.6 × 10^(-13) Coulombs/sec and each photon emits one electron.
The charge per photon can be calculated using the equation:
Energy of a photon = Planck's constant × Speed of light / Wavelength
Given that the wavelength of the light is 570 nm (or 570 × 10^(-9) meters), Planck's constant is 6.626 × 10^(-34) Js, and the speed of light is 3 × 10^8 m/s, we can calculate the energy of a photon:
Energy of a photon = (6.626 × 10^(-34) Js) × (3 × 10^8 m/s) / (570 × 10^(-9) m)
Now, we can calculate the charge per photon using the equation:
Charge per photon = Energy of a photon / Work function of the material
Since the question does not provide any information about the work function of the material, we cannot calculate the exact charge per photon. However, if we assume that the work function is negligible, we can ignore this term and assume that each photon emits one electron, so the charge per photon is equal to the elementary charge e, which is approximately 1.6 × 10^(-19) Coulombs.
Finally, we can substitute the calculated values into the first equation:
Number of photons per second = (6.6 × 10^(-13) Coulombs/sec) / (1.6 × 10^(-19) Coulombs)
Thus, the number of photons per second striking the photocell is approximately 4.125 × 10^6 photons/sec.