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Parallel (identical Cells)
Identical cells in parallel provide approximately the same e.m.f. as one cell while sharing current demand and reducing effective internal resistance.
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Parallel (identical Cells)
Recommended for Class 10
Parallel (identical Cells)
Identical cells can be connected in parallel by joining corresponding positive terminals together and corresponding negative terminals together.
For ideal identical cells, the parallel combination provides approximately the same e.m.f. as one cell.
Example
If each identical cell has an e.m.f. of:
1.5 V
then an ideal parallel arrangement also has approximately:
1.5 V
It does not become 3.0 V simply because two identical cells are connected in parallel.
Why Use Parallel Cells?
In a practical model, parallel identical cells can share the current demand and provide greater effective capacity/runtime than one cell.
Their effective internal resistance can also be reduced.
For `n` identical cells each having internal resistance `r`:
**req = rn**
Series Comparison
Identical cells in series:
e.m.f.s add.
Identical cells in parallel:
e.m.f. remains approximately that of one cell.
Important Condition
Cells connected directly in parallel should be suitably matched. Cells with significantly different e.m.f.s should not simply be connected together because unwanted currents can flow between them.
Parallel (identical Cells) — Advanced
Common Mistakes
Common Mistakes
- Mistake
Mistake: Parallel cells add their voltages like series cells. Correction: Parallel cells do not add their voltages like series cells.
Revision Zone
60-Second Revision
Quick cues from this topic — use them for last-minute revision.
Cells series → voltage adds.
Identical cells parallel → same e.m.f.
Parallel → can supply/share more current capacity.
- Definition
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Practice
PQ
Q1. Explain identical cells in parallel.
PQ
Q2. Two 1.5 V cells parallel.
PQ
Q3. Two 1.5 V cells series.
PQ
Q4. State internal-resistance effect.
PQ
Q5. Explain why unmatched cells should not simply be paralleled.
Exam Practice
EQ
Q1. Compare cells in series and parallel.
EQ
Q2. State emf of parallel identical cells.
EQ
Q3. Explain current-sharing advantage.
EQ
Q4. Calculate r_eq.
EQ
Q5. Explain matching requirement.
School-standard facts for Matric and Intermediate. Original explanations — not copied from textbooks.