A circuit contains a 12V battery and two resistors of 4Ω and 6Ω in parallel. Wha
Practice Questions
Q1
A circuit contains a 12V battery and two resistors of 4Ω and 6Ω in parallel. What is the total current supplied by the battery? (2019)
1.2 A
2 A
3 A
4 A
Questions & Step-by-Step Solutions
A circuit contains a 12V battery and two resistors of 4Ω and 6Ω in parallel. What is the total current supplied by the battery? (2019)
Step 1: Identify the values given in the problem. We have a 12V battery and two resistors: one is 4Ω and the other is 6Ω.
Step 2: Understand that the resistors are in parallel. This means we need to find the equivalent resistance (R_eq) using the formula for parallel resistors.
Step 3: Use the formula for equivalent resistance in parallel: R_eq = 1 / (1/R1 + 1/R2). Here, R1 is 4Ω and R2 is 6Ω.
Step 4: Calculate 1/R1 and 1/R2: 1/4 = 0.25 and 1/6 ≈ 0.1667.
Step 5: Add these two values together: 0.25 + 0.1667 = 0.4167.
Step 6: Take the reciprocal of the sum to find R_eq: R_eq = 1 / 0.4167 ≈ 2.4Ω.
Step 7: Now, use Ohm's Law to find the total current (I) supplied by the battery. The formula is I = V / R_eq.
Step 8: Substitute the values into the formula: I = 12V / 2.4Ω.
Step 9: Calculate the current: I = 5 A.
Ohm's Law – The relationship between voltage, current, and resistance in an electrical circuit, expressed as V = I * R.
Equivalent Resistance in Parallel Circuits – The method to calculate the total resistance of resistors connected in parallel, using the formula 1/R_eq = 1/R1 + 1/R2.
