PHYSICS · Multi-part · Fermi University Physics · Scientific Practice & Experimental Methods · Electronics, Instrumentation & Communication · Quantities, units and the practice of measurement
Measurement and Method, Ch The instrument: resolution, sensitivity, calibration and traceability
Problem
Two resistors, each 500kΩ, are connected in series across a 9.00V source. A voltmeter of internal resistance 1.00MΩ is connected across the midpoint of the two resistors, in parallel with the lower one, to read the potential there.
((a)) State the true midpoint potential with no voltmeter connected.
((b)) Estimate the potential the voltmeter actually reads once it is connected, treating the meter's resistance and the lower resistor as being in parallel.
((c)) State whether the loading is large enough that the reading needs correcting before it is quoted, giving your reasoning.