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6 Ω और 3 Ω के दो प्रतिरोधक 12 V सप्लाई के पार समांतर में जुड़े हैं। तब
1. समतुल्य प्रतिरोध 2 Ω है।
2. कुल करंट 6 A है।
3. 3 Ω प्रतिरोधक से करंट 4 A है।
4. खपत शक्ति 72 W है।
उपरोक्त में से कौन-सा/से कथन सही है/हैं?

उत्तर और चरणबद्ध हल
सही उत्तर: D. उपरोक्त सभी
संक्षिप्त व्याख्या

6 Ω || 3 Ω के लिए Req=(6×3)/(6+3)=2 Ω, कुल करंट=12/2=6 A, 3 Ω से करंट=12/3=4 A और P=12×6=72 W। मुख्य संबंध: 1/R_eq=Σ(1/R_i); I_i=V/R_i; P=V·I।

परीक्षा फोकस: समांतर में हर प्रतिरोधक पर समान वोल्टेज होता है। सामान्य गलती: समांतर प्रतिरोधों को सीधे जोड़ना।

विस्तृत हल (मूल भाषा में)

Statement-wise Verification

  • Statement 1 - Correct.
    Equivalent resistance is 2 Ω.
    Equivalent resistance is found from reciprocal addition, total current is the sum of branch currents, and total real power is the sum of branch powers.
  • Statement 2 - Correct.
    Total current is 6 A.
    Total current=12/2=6 A.
  • Statement 3 - Correct.
    Current through 3 Ω resistor is 4 A.
    The 3 Ω branch current=12/3=4 A.
  • Statement 4 - Correct.
    Power consumed is 72 W.
    Total power=12×6=72 W.

Core Concept

Parallel branches share the same voltage. Equivalent resistance is found from reciprocal addition, total current is the sum of branch currents, and total real power is the sum of branch powers.

Formula / Key Relationship

1/R_eq=Σ(1/R_i); I_i=V/R_i; P_total=V I_total.

Step-by-Step Check

For 6 Ω || 3 Ω, Req=(6×3)/(6+3)=2 Ω. Total current=12/2=6 A. The 3 Ω branch current=12/3=4 A. Total power=12×6=72 W.

Why the Other Options Are Wrong

Option A is incorrect because it omits correct statement(s) 3, 4. Option B is incorrect because it omits correct statement(s) 4. Option C is incorrect because it omits correct statement(s) 1, 3.

Exam Shortcut / Approach

Solve branch currents first when the same supply voltage appears across every resistor.

Common Mistake

Adding parallel resistances directly is incorrect.

Quick Revision

Parallel Resistor Current and Power is linked with Parallel Resistance, DC Circuits and Basic Electrical Engineering. Solve branch currents first when the same supply voltage appears across every resistor.

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