Q129 / 200 · NEET 2005 · Physics
Two batteries, one of emf 18 volts and internal resistance $2 \Omega$ and the other of emf 12 volts and internal resistance $1 \Omega$, are connected as shown. The voltmeter $V$ will record a reading of:
- A30 volt
- B18 volt
- C15 volt
- Correct answerD14 volt
Solution
Reading of voltmeter
$$
=\frac{\frac{E_1}{r_1}+\frac{E_2}{r_2}}{\frac{1}{r_1}+\frac{1}{r_2}}=\frac{E_1 r_2+E_2 r_1}{r_1+r_2}
$$
Putting value we get 14 volt.
Hence, the correct answer is option: 'D'.