Q1. [4] § 11.6 RESISTANCE OF A SYSTEM OF RESISTORS § 11.6.1 Resistors in Series § 11.6.2 Resistors in Parallel
Two resistors X (3 Ω) and Y (6 Ω) joined in series with a battery of 2 V, along with a voltmeter and ammeter.
Study the circuit shown in which two resistors X and Y of resistances 3 Ω and 6 Ω respectively are joined in series with a battery of 2 V.
- (I) Draw a circuit diagram showing the above two resistors X and Y joined in parallel with same battery and same ammeter and voltmeter. [1]
- (II) In which combination of resistors will the (i) potential difference across X and Y and (ii) current through X and Y, be the same ? [1]
- (III) Answer either (a) or (b). [2]
Previously asked in CBSE board exam
2025 31/6/1 Q39
Generated by claude-sonnet-4-6 · 2026-06-15 06:45 · grounding stimulus
Model Answer
(I) Parallel Circuit Diagram:
```
+----[3Ω X]----+
| |
+---+----[6Ω Y]----+---[A]---+
| |
+----------[2V battery]-------+
| |
+----[V]----+
```
(Voltmeter connected across both resistors in parallel; ammeter in series with the main line)
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(II)
- Parallel combination: potential difference (voltage) across X and Y will be the same.
- Series combination: current through X and Y will be the same.
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*(III)(a) OR (b) — [Student to attempt one as per their question paper; sub-question (a)/(b) text not provided in the extract above.]
Source: Chapter 11 – Electricity, NCERT Science Class 10
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Explanation
- For (I), examiners check that both resistors are drawn in parallel branches, voltmeter is across the parallel combination, and ammeter is in the main (series) line.
- For (II), remember the two key rules: in series → same current everywhere; in parallel → same voltage across each branch. These are the most commonly tested lines from this topic.
- For (III), since the actual (a)/(b) options were not printed in the extract, attempt whichever sub-question your paper provides (likely a calculation of equivalent resistance or current).
If a question refers to an image, map, graph or diagram that is not shown here, find the actual CBSE question paper on the CBSE website:
cbse.gov.in.