If a series circuit has a current of about 15.4 mA and a source voltage of 20 V, the total resistance is approximately:

To find the total resistance in a series circuit, Ohm's Law is applied, which states that Voltage (V) equals Current (I) multiplied by Resistance (R):

[ V = I \times R ]

We can rearrange this formula to solve for resistance:

[ R = \frac{V}{I} ]

In this case, the source voltage is 20 V, and the current is approximately 15.4 mA. It is important to convert the current from milliamps to amps for consistency in units:

[ 15.4 , \text{mA} = 0.0154 , \text{A} ]

Now, substituting the values into the formula:

[ R = \frac{20 , \text{V}}{0.0154 , \text{A}} ]

Calculating this gives:

[ R = \frac{20}{0.0154} \approx 1298.7 , \text{ohms} ]

This value rounds to approximately 1300 ohms, confirming that the choice indicating 1300 ohms accurately reflects the calculated total resistance in the circuit.

This methodical approach illustrates how Oh