A 2kΩ resistor is connected across a 12V battery of negligible internal resistance.
(a) Calculate the true potential difference across the resistor when no measuring instrument is attached.
(b) A voltmeter of internal resistance 4kΩ is now connected across the same resistor. Determine the reading shown by the voltmeter.
(c) Compute the percentage error introduced by the voltmeter in measuring the potential difference across the resistor.
(d) State, with calculation–based justification, whether this voltmeter is suitable for measuring the stated voltage across the given resistor.