Calculation of Current through the 12 ohm Resistor

To determine the current flowing through the 12 ohm resistor in a circuit with a 9V battery and other resistors, we need to follow a step-by-step process. Let's break it down:

Step 1: Calculate the Total Resistance
- When resistors are connected in series, their resistances add up. So, we need to calculate the total resistance of the circuit.
- The total resistance (Rt) is given by the sum of individual resistances: Rt = R1 + R2 + R3 + R4 + R5.
- In this case, R1 = 0.2 ohm, R2 = 0.3 ohm, R3 = 0.4 ohm, R4 = 0.5 ohm, and R5 = 12 ohm.
- Plugging in these values, we get: Rt = 0.2 + 0.3 + 0.4 + 0.5 + 12 = 13.4 ohm.

Step 2: Apply Ohm's Law to Calculate Current
- Ohm's Law states that the current flowing through a circuit is equal to the voltage applied divided by the total resistance: I = V / R.
- In this case, the voltage (V) is 9V (given by the 9V battery) and the total resistance (R) is 13.4 ohm (calculated in Step 1).
- Substituting these values in the equation, we find: I = 9 / 13.4 ≈ 0.672 amps.

Step 3: Determine the Current through the 12 ohm Resistor
- Since the resistors are connected in series, the same current flows through each resistor in the circuit.
- Therefore, the current flowing through the 12 ohm resistor is the same as the current calculated in Step 2.
- Hence, the current through the 12 ohm resistor is approximately 0.672 amps.

Summary:
In a circuit with a 9V battery and resistors of 0.2, 0.3, 0.4, 0.5, and 12 ohm connected in series, the total resistance is 13.4 ohm. According to Ohm's Law, the current flowing through the circuit is 0.672 amps. Since the resistors are connected in series, the same current flows through each resistor, including the 12 ohm resistor. Therefore, the current passing through the 12 ohm resistor is also approximately 0.672 amps.