Question

A radio-set of resistance 20 $\Omega$and a resistor of 4 $\Omega$ are connected in series with a 6V battery. What is the potential difference across the radio-set?

• A. 24V
• B. 120V
• C. 80V
• D. 5V

Answer 1

The correct option is D 5V

Answer is D.
In series.
$R_{total}=R_1+R_2...R_n$.
In this case, the total resistance is 20+4 = 24 ohms.
The total current in the circuit is calculated from the relation V = IR, that is, I=V/R.
I = 6 V/24 ohms = 0.25 A.
As it is a series connection, the current through each of the components is the same, the voltage across the circuit is the sum of the voltages across each component.
So, the voltage across the radio set is calculated as follows.
The current is 0.25 A and the resistance of the radio set is 20 ohms.
Therefore, V=IR = 0.25 * 20 = 5 V.
Hence, the potential difference across the radio-set is 5 V.