Question

How do you calculate current in a series circuit?

Answer 1

In a series circuit, calculating the current is straightforward because the current is the same at every point in the circuit. The formula for calculating current in a series circuit is based on **Ohm’s Law**, which states:

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

Where:
- \( I \) is the current (in amperes),
- \( V \) is the total voltage applied across the circuit (in volts),
- \( R \) is the total resistance of the circuit (in ohms).

### Steps to Calculate Current in a Series Circuit:
1. **Find the total resistance (R):**
   In a series circuit, the total resistance is the sum of the resistances of all the components connected in series:
   \[
   R_{total} = R_1 + R_2 + R_3 + \dots
   \]
   
2. **Determine the total voltage (V):**
   This is the voltage of the power supply or battery connected to the circuit.

3. **Apply Ohm’s Law:**
   Once you have the total resistance and total voltage, use the equation \( I = \frac{V}{R} \) to calculate the current.

### Example:
If a series circuit has a total voltage of 12 V and a total resistance of 4 ohms:
\[
I = \frac{12 \, V}{4 \, \Omega} = 3 \, \text{A}
\]
The current in the circuit is 3 amperes.

Since the current in a series circuit is the same throughout, each component in the series will have this same 3 A of current flowing through it.

Answer 2

To calculate the current in a series circuit, you can use Ohm's Law, which states:

\[ I = \frac{V_{total}}{R_{total}} \]

where:
- \( I \) is the current,
- \( V_{total} \) is the total voltage supplied by the power source,
- \( R_{total} \) is the total resistance of the circuit.

In a series circuit, the total resistance is the sum of the individual resistances:

\[ R_{total} = R_1 + R_2 + R_3 + \ldots + R_n \]

So, to find the current:

1. Add up all the resistances in the series circuit to find \( R_{total} \).
2. Divide the total voltage \( V_{total} \) by \( R_{total} \) to get the current \( I \).