Instructions

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Circuit 6: Current measurement with a greater shunt resistance
Setup information
Install the three resistors and then the two jumpers as shown in Fig. 2.6. Connect the moving-coil instru-
ment. Check the placement on the board again and only then connect the battery.
Components required:
2 x 10 kΩ resistor,
1 x 220 Ω resistor,
1 x moving-coil instrument,
1 x breadboard, 1 x 9V bat-
tery with clip connector
Fig. 2.6: Current measurement
with a greater shunt resistance
Experiment
Once the battery is connected, the moving-coil instrument will deflect. What is the scale of the deflection?
If everything is fine, the needle will move about half-way. Unlike the previous experiment, here the meter
now has a 220 Ω resistor connected in parallel. Part of the current flow – approximately half of it – is now
diverted by this resistor and will no longer flow through the meter. The circuit diagram for this experiment is
shown in Chap. 3, Fig. 3.6.