A series circuit contains three 2 Ω resistors and a 6 Ω resistor. The current in each resistor is 4.0 A. What is the voltage of the battery in the circuit? 2.0 V 3.0 V 32 V 48 V

The effective resistance of several resistors in series

is the sum of their individual resistances.

In this circuit, the effective resistance is

(2 ohms + 2 ohms + 2 ohms + 6 ohms) = 12 Ω.

So 12 ohms is what the battery sees. The battery doesn't know

whether that's a single resistor, or the sum of several.

Now, the voltage across a resistor is

V = (current) · (resistance).

For this circuit ...

V = (4.0 A) (12 Ω) = 48 volts.