A battery with internal resistance is connected to a external resistor
PHYSICS · Multi-part · CBSE · Physics · Current Electricity · Current Electricity
Problem
A 12.0V battery with internal resistance 2.0Ω is connected to a 98Ω external resistor. To measure the circuit current, two ammeters are available: ammeter A1 with internal resistance 0.50Ω, and ammeter A2 with internal resistance 2.0Ω. Each ammeter is inserted separately, in turn, in series with the external resistor.
(a) Calculate the current that would flow through the external resistor if no ammeter were present.
(b) Determine the reading shown by A1 when it is placed in the circuit. Show all steps clearly and include appropriate units.
(c) Determine the reading shown by A2 when it is placed in the circuit. Show all steps clearly and include appropriate units.
(d) Using your results, identify which ammeter provides a measurement closer to the true current found in part (a). Support your answer quantitatively by computing the percent error for each ammeter and explaining the relationship between internal resistance and measurement accuracy.