How do I determine the EMF and internal resistance of a solar cell?

Question

Describe the experimental setup, the quantities to be measured, and the calculations required to determine the EMF and internal resistance.

Answer 1

You can measure the EMF (voltage) output of a solar cell with a DC Voltmeter. To measure the internal resistance, you will need a presision resistor and an amp meter. Connect the precision resistor and the amp meter in series across the solar cell. Measure the current and the voltage. the total resistance in the circuit will be the voltage divided by the current (ohms law: R=E/I) Since the precision resistor, the internal resistance of the amp meter and the internal resistance of the solar cell form a series circuit, you can solve for the internal resistance of the solar cell by subtracting the value of the precision resistor and the value of the internal resistance of the amp meter.

Rt=Ri+Rp+Rshunt

I'll make up an example:

if the EMF is 0.6V and the current measured is 2.4mA, then the Total resistance would be 250ohms

If the precision resistor is 249ohms and the internal resistance of the amp meter is 0.1ohms, then the internal resistance of the solar cell would be 0.9 ohms. 250-249-0.1=0.9

JeffM

Answer 2

i do no longer know what 'e=a million.5B ' skill. i will anticipate that's a mistake and you propose emf = a million.5V. you haven't any longer given the contraptions for resistance. i will anticipate that's ohms (?), yet you may desire to verify it extremely is no longer k? or something else. _________________ If the three cells have been pointing a similar way, the finished emf could be a million.5+a million.5+a million.5 = 4.5V. yet via fact one has reversed polarity, the finished emf is a million.5+a million.5-a million.5 = a million.5V So the finished emf = a million.5V via fact the cells are in sequence the finished inner resistance =0.a million+0.a million+0.a million = 0.3? the finished circuit resistance, R = 6+0.3 = 6.3? the present is a similar by way of all components (on account that's a chain circuit). modern-day = emf/R = a million.5/6.3 = 0.24A

Answer 3

You can determine the internal resistance with a multi-meter, as far as the emf, you got me. Let me know.

Answer 4

Jeff M's answer is absolutely correct and complete.Hope you got the idea.