A circuit with a voltage source and two identical resistors in series has a total resistance of 30 ohms. A third resistor is added in series. If the new total resistance is 45 ohms, what is the resistance of the third resistor?
Q1. A circuit with a voltage source and two identical resistors in series has a total resistance of 30 ohms. A third resistor is added in series. If the new total resistance is 45 ohms, what is the resistance of the third resistor?
Answer: 18 ohms
Explanation: The resistance of the third resistor can be found by subtracting the initial total resistance from the new total resistance, resulting in a 15-ohm increase.