In a circuit with a 12V battery and two resistors in series (R1 = 4Ω, R2 = 8Ω),
Practice Questions
Q1
In a circuit with a 12V battery and two resistors in series (R1 = 4Ω, R2 = 8Ω), what is the voltage across R2?
4V
6V
8V
12V
Questions & Step-by-Step Solutions
In a circuit with a 12V battery and two resistors in series (R1 = 4Ω, R2 = 8Ω), what is the voltage across R2?
Correct Answer: 8V
Step 1: Identify the values given in the problem. We have a 12V battery, R1 = 4Ω, and R2 = 8Ω.
Step 2: Calculate the total resistance in the circuit. Since the resistors are in series, add R1 and R2 together: R_total = R1 + R2 = 4Ω + 8Ω.
Step 3: Calculate the total resistance: R_total = 4Ω + 8Ω = 12Ω.
Step 4: Use Ohm's Law to find the current in the circuit. Ohm's Law states that I = V / R. Here, V is the total voltage (12V) and R is the total resistance (12Ω). So, I = 12V / 12Ω.
Step 5: Calculate the current: I = 12V / 12Ω = 1A.
Step 6: Now, find the voltage across R2 using Ohm's Law again. The formula is V_R2 = I * R2. We already found I = 1A and R2 = 8Ω.
Step 7: Calculate the voltage across R2: V_R2 = 1A * 8Ω = 8V.
