Experiment 6 - The Real Battery

What are the characteristics of a real battery? And what impact has this on the circuit from the experiment 4?

Measure the voltage across the load resistor. Contrast this with the voltage of the battery without load resistor.

Measuring the voltage of 9 volts battery with without load. (Enlarge)

Measuring the voltage across the load resistor. (Enlarge)

Circuit diagram measuring the voltage of 9 volts battery with without load. Circuit diagram measuring the voltage across the load resistor.

The voltage of the battery without load is 9 V. In the load circuit however you measure a voltage at the load resistance of only 8 V.

Somewhere in the circuit a voltage of 1 V is applied. From the experiment 4 you know, that a current of 0.8 A flows in the circuit. According to Ohm's law the "hidden" resistance is of a value of...

R_i = U_i / I = 1 V / 0.8 A = 1.2 Ω

This resistance can reside only in the battery...