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Can someone please help me with this question on the photoelectric effect?

The photocell is connected to a 12V d.c. supply through a very sensitive ammeter. Light of wavelength 4.2 x 10^-7m shines on plate A. The plate absorbs 1.2 x 10^-6 J of light energy every second. One per cent of the absorbed photons cause electrons to be emitted from the plate. Estimate the current in the circuit.

Energy of photon= 5 x 10^-19 J

Thank you in advance.
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KaylaJ
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The total energy absorbed by the plate is 1.2 x 10^-6 J, since each photon arriving at the plate has 5 x 10^-19J,

Number of photons per second = 1.2 x 10^-6J / 5 x 10 ^-19J = 2.4 x 10^12 photons
1 percent of this = 0.01 x 2.4 x 10^12 = 2.4 x 10^10 photons

Therefore there are 2.4 x 10^10 electrons emitted from the photoelectric plate per second.

Since I = ne (Current = Number of electrons x charge on each electron)
Estimate of current = (2.4 x 10^10) x (1.6 x 10^-19) = 3.84 x 10 ^-9 A

I hope this helped.

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