Measuring Voltage, Current, and Resistance
Point: Familiarization with a digital multimeter (DMM)
Measuring Voltages Measure voltage across 100 Ω and 1000 Ω resistors
(independent circuits) using set voltages of 0.5 V to 6 V in 0.5 volt steps.
Is there a difference in the voltage readings between the two resistors for
the same voltage settings? If so, how big is this difference? Is there internal
resistance in the power supply? Can you determine it?
Measuring Current Measure the current through the 100 Ω resistor over the
same voltage range. At the lowest voltage setting, read the current on different
scales. Is there a difference in value (not just sensitivity)? Can you explain this
difference in term’s of the meter’s input resistance?
Graph I vs V and determine R.
Measuring Resistance Measure the resistance and compare with I vs V
determination. Does the DMM measurement depend on the scale (other than
sensitivity)?
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