Question

A current is passed through two coils connected in series. The potential difference across the first coil is 3 V and that of the second coil 4.5V. If the first coil has a resistance of 2 ohms, the resistance of the second coil is

• A. 3$\Omega$
• B. 5$\Omega$
• C. 7$\Omega$
• D. 9$\Omega$

Answer 1

The correct option is A 3$\Omega$

$P.D\propto R$

$\frac{P.D_1}{P.D_2}=\frac{R_1}{R_2}$

$\frac{3}{4.5}=\frac{2}{R_2}$

$R_2=3\Omega$