Question

Current supplied by the cell in the adjoining figure is

• A. 1.5 A
• B. 1 A
• C. 0.1 A
• D. 0.5 A

Answer 1

Answer: (C)

0.1 A

Answer 2

The circuit has two branches connected across a 2 V cell:

• One branch: a single 30 Ω resistor.
• Other branch: two 30 Ω resistors in series giving 60 Ω.

Their equivalent resistance is

$$R_{eq} = \left(\frac{1}{30}+\frac{1}{60}\right)^{-1} = \left(\frac{2+1}{60}\right)^{-1} = \frac{60}{3} = 20\,\Omega.$$

Thus, the current supplied by the cell is

$$I = \frac{V}{R_{eq}} = \frac{2\,V}{20\,\Omega} = 0.1\,A.$$