For an electric circuit given below, the correct combination of voltage (V) and current (I) is

Question

Question

This question was previously asked in

NDA-II 2024 (GAT) Official Paper (Held On: 01 Sept, 2024)

Answer 1

CONCEPT:

Parallel Circuits and Ohm’s Law

In a parallel circuit, the total voltage across each branch is the same.
To calculate total current, we first find the equivalent resistance (R_eq) of the parallel combination.
Then apply Ohm’s Law: V = IR or I = V / R

EXPLANATION:

1. Equivalent Resistance:
The three resistors 100 Ω, 200 Ω, and 300 Ω are in parallel.

1/R_eq = 1/100 + 1/200 + 1/300

LCM = 600 → (6 + 3 + 2)/600 = 11/600

R_eq = 600/11 ≈ 54.55 Ω
2. Voltage Calculation:
Using Ohm’s Law: V = IR

The current through 100 Ω resistor is given as 3 A, hence:

V = 100 × 3 = 300 V
3. Total Current Calculation:
Now calculate current through each resistor using V = 300 V:
- 100 Ω → I = 300 / 100 = 3 A
- 200 Ω → I = 300 / 200 = 1.5 A
- 300 Ω → I = 300 / 300 = 1 A
Total I = 3 + 1.5 + 1 = 5.5 A

Therefore, the correct answer is: Option 2) V = 300 V ; I = 5.5 A