(8c27p22) A solar cell generates a potential difference of 0.1397 V when a 500 r

Question

(8c27p22) A solar cell generates a potential difference of 0.1397 V when a 500 resistor is connected across it, and a potential difference of 0.2120 V when a 1000 resistor is substituted.
What is the internal resistance of the solar cell?
1.08×103 ohms What is the emf of the solar cell?
4.40×10-1 V The area of the cell is 5.0 cm2, and the rate per unit area at which it receives energy from light is 2.0m W/ cm2. What is the efficiency of the cell for converting the light energy to thermal energy in the 1000 external resistor? (percent = Do not enter a unit)

You are correct.
Your receipt no. is 159-4012 Previous Tries You are correct.
Your receipt no. is 159-4100 Previous Tries Incorrect. Tries 7/99 Previous Tries

Explanation / Answer

emf of the solar cell emf = 4.40*10^-1 V

internal resistance R = 1.08*10^3 ohm

Area = 5.00*10^-4 m^2

Intensity I = 20.00 W/m^2

hence the power P = I*A = 10^-2 W.

External resistance Rex = 1000 ohm.

hence power from the voltage = emf^2/(R+Rex) = 0.44^2/(1080+1000) = 9.308*10^-5 W

hence efficiency e = out/in =  9.308*10^-5 /10^-2 = 9.04*10^-3 = 0.90 %

Related Questions

Navigate

• Browse (All)
• Browse #
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.