Distinguish between potentiometer and voltmeter.
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Solution and Explanation
1. Measures potential difference without drawing current from the circuit, using a null point method.
2. Provides high accuracy as it balances the unknown voltage against a known voltage gradient.
Voltmeter:
1. Measures potential difference by drawing a small current, as it is connected in parallel.
2. Less accurate due to its finite resistance, which affects the circuit.
Answer: Potentiometer measures voltage at null point without current draw, offering higher accuracy; voltmeter draws current and is less accurate.
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