Three similar cells each of e.m.f 2 v and internal resistance 2Ω are connected in parallel, the total e.m.f and total internal resistance are respectively

Analyze the question: Three identical cells, each with e.m.f. 2 V and internal resistance 2 Ω, are connected in parallel. We need the total e.m.f. and the total internal resistance.

Concept:

• For identical cells in parallel, the total e.m.f. equals the e.m.f. of a single cell (the voltage does not add up).
• The internal resistances combine like parallel resistors, so the total internal resistance falls.

Formula for n identical cells in parallel:

• E_total = E
• r_total = r / n

Solution:

1. Total e.m.f. = 2 V

2. Total internal resistance: 1/r_total = 1/2 + 1/2 + 1/2 = 3/2 r_total = 2/3 ≈ 0.67 Ω ≈ 0.7 Ω

So the total e.m.f. is 2 V and the total internal resistance is about 0.7 Ω.

Answer: Option B (2 V, 0.7 Ω).

Tip: Remember it this way:

• Series → e.m.f. adds (6 V) and internal resistance adds (6 Ω).
• Parallel → e.m.f. stays the same (2 V) and internal resistance shrinks (r/n).

Options A and C are wrong because they use the series resistance of 6 Ω. Option D has the wrong e.m.f. of 6 V.