What is the primary function of the rheostat in the Ohm's law verification circuit?
ATo measure current directly
BTo measure potential difference across the conductor
CTo vary the resistance and hence adjust the current in the circuit
DTo open the circuit permanently
Answer & Solution
Correct answer: C. To vary the resistance and hence adjust the current in the circuit
A rheostat is a variable resistor. In this experiment, it is adjusted to change the circuit resistance, thereby changing the current so that different pairs of $V$ and $I$ can be recorded.
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