How do I solve for this 12 (12 points). An engineer is designing a new sodium ph

Question

How do I solve for this 12 (12 points). An engineer is designing a new sodium photocathode for a night vision scope. She uses the experiment shown below to measure the voltage and current from the metallic emitter as a function of both the power of the light and wavelength of the light that hits the emitter. She assumes that all the electrons emitted go to the collector. Fill out the tables below with the results the engineer expects to take to her manager to characterize the device her company is building. The wavelength of sodium is 589 nm. Metallic emitter Light Collector SensitiveA ammeter (2.orten It) 1.00 (1). If the wavelength and the power of the incident light are 500 nm and 10 mW, respectively The expected measured current is A)4.03 x 10 Amperes B. 4.03 x 10 Amperes; (C). 0 Amperes; (D), 2.02 × 102 Amperes; E)2.02 x 10 Amperes; -2

Explanation / Answer

when power of light ,P = 0.1 mW, wavelength = 600 nm = lambda
then if n photons hit photocathode per second
n*hc/lambda = P
then 0.1*10^-3 = nhc/600*10^-9 [ h = 6.63*10^-34 (planks constant) , c is speed of light, 3*10^8 m/s]

putting in values, n = 3.0165*10^14 photons per second
expected current, i = n*e [ assuming every photon releases an electroin, e is charge on electron ]
i = n*1.6*10^-19 = 4.82*10^-5 A

Voltage, V = iR ( R = 1 ohm)
V = 4.82*10^-5 V

when power of light ,P = 1 mW, wavelength = 550 nm = lambda
then if n photons hit photocathode per second
n*hc/lambda = P
then 10^-3 = nhc/550*10^-9 [ h = 6.63*10^-34 (planks constant) , c is speed of light, 3*10^8 m/s]

putting in values, n = 27.65*10^14 photons per second
expected current, i = n*e [ assuming every photon releases an electroin, e is charge on electron ]
i = n*1.6*10^-19 = 4.42*10^-4 A

Voltage, V = iR ( R = 1 ohm)
V = 4.42*10^-4 V

when power of light ,P = 10 mW, wavelength = 450 nm = lambda
then if n photons hit photocathode per second
n*hc/lambda = P
then 10*10^-3 = nhc/450*10^-9 [ h = 6.63*10^-34 (planks constant) , c is speed of light, 3*10^8 m/s]

putting in values, n = 226.244*10^14 photons per second
expected current, i = n*e [ assuming every photon releases an electroin, e is charge on electron ]
i = n*1.6*10^-19 = 36.199*10^-4 A

Voltage, V = iR ( R = 1 ohm)
V = 36.199*10^-4 V

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