Question

A battery, an open switch and a resistor are connected in series as shown in figure. Consider the following three statements concerning the circuit. A voltmeter will read zero if it is connected across points (i) $P$ and $T$ (ii) $P$ and $Q$ (iii) $Q$ and $T$ Which one of the above is/are true ?

• A. only (i)
• B. only (iii)
• C. only (i) and (iii)
• D. (i), (ii) and (iii)

Answer 1

Answer: (C)

only (i) and (iii)

Answer 2

When the switch is not closed, a voltmeter connected across $P$ and $T$ will not show any potential difference. Between $Q$ and $T$ also there is no potential difference because circuit is not complete. Therefore in both the cases, the voltmeter will read zero. Between $P$ and $Q$, the emf of the battery will be given.