A student has to measure the current through and the potential difference across a 5Ω resistor that is connected to a 6V battery of negligible internal resistance.
(i) Draw a neat and labelled circuit diagram showing the correct placement of an ammeter and a voltmeter for this purpose.
(ii) Explain, with reference to the typical resistance of each instrument, why the ammeter must be placed in one position and the voltmeter in the other so that the original circuit conditions are least disturbed.
(iii) If the voltmeter were mistakenly connected in series with the resistor while the ammeter remained correctly connected, state qualitatively (a) whether the circuit current would increase, decrease or remain the same, and (b) what the voltmeter would read. Justify your answers.