Experiment 12  Discharging Battery
In the following three experiments you discharge the battery.
For this you leave the battery connected to a load circuit for a longer period of time.
You watch the internal resistance and how it changes with time.
In the experiments, you measure two values...

The voltage U_{0}
of the battery without a load circuit and

the current I through the load circuit.
From this you can calculate the internal resistance
R_{i}...
R_{i} =
( U_{0} / I )  R_{L}
(Where does this formula come from...?...see Experiment 18 in the
section "Know more...")
At the charged battery
you measure a voltage
U_{0} of 9 V.
In a second step you measure a current
through the load circuit of I = 0.8 A.
Hence you calculate the internal resistor
R_{i} =
1.2 Ω.

Measuring the voltage U_{0} of the battery without a load circuit.
Measurement of the current I in a load circuit.

Circuit for measuring the voltage U_{0} of the battery without a load circuit.
(Enlarge) 
Circuit for measuring the current I in a load circuit.
(Enlarge) 
In the next step you start to discharge the battery...