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Test your understanding of CBSE Class 10 Physics Chapter 12 — Electricity with this MCQ quiz. It covers Ohm's Law (V = IR), factors affecting resistance, resistors in series and parallel, and domestic electric circuits. All 8 questions are aligned to the NCERT textbook and include previous year CBSE board questions from 2022 to 2026, with detailed answer explanations.

Subject Physics — Class 10 CBSE Chapter 12 — Electricity
Questions 8 MCQs (Set 1) PYQ Years CBSE 2022–2026
Difficulty L1 (Easy) to L3 (Hard) Type Conceptual · Numerical · Case Study

Topics covered in this Class 10 Electricity quiz

  • Ohm's Law (V = IR) and its three forms
  • Resistance and resistivity — formula R = ρL/A
  • Factors affecting resistance: length, cross-section, material, temperature
  • Resistors in series — equivalent resistance formula
  • Resistors in parallel — equivalent resistance formula
  • Domestic electric circuits — 230 V AC, parallel connection of appliances
  • Electric fuses — ratings, working, and selection
  • Assertion–reason and case study based MCQs (CBSE 2023–2026 pattern)

Sample questions from this quiz

Q1.  According to Ohm's Law, which of the following correctly relates potential difference (V), current (I), and resistance (R)?

(A) V = I + R    (B) V = I × R    (C) V = I / R    (D) V = I² / R

Q2.  Three identical resistors, each of resistance R, are connected in parallel. The equivalent resistance of the combination is:

(A) 3R    (B) R    (C) R/3    (D) R/2

Q3.  A copper wire of resistance 16 Ω is stretched uniformly until its length doubles (volume remains constant). The new resistance of the wire is:

(A) 8 Ω    (B) 32 Ω    (C) 64 Ω    (D) 4 Ω

↓ Take the full quiz below for all 8 questions with instant feedback, answer explanations, and a timer ↓

Physics · Class 10
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Difficulty: L1 — Direct L2 — Standard L3 — Tricky L4 — HOTs
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Key formulas — CBSE Class 10 Electricity (Chapter 12)

Formula name Expression Used for
Ohm's Law V = IR Relating voltage, current, resistance
Resistance formula R = ρL / A Effect of length, area, resistivity on R
Series resistance Req = R₁ + R₂ + R₃ Total resistance of series circuit
Parallel resistance 1/Req = 1/R₁ + 1/R₂ + 1/R₃ Total resistance of parallel circuit
Electric power P = VI = I²R = V²/R Power consumed by an appliance
Stretched wire R′ = n² × R If wire is stretched to n× its length (constant volume)

Frequently asked questions — Electricity Class 10

What is Ohm's Law for Class 10 CBSE?

Ohm's Law states that the potential difference (V) across a conductor is directly proportional to the current (I) flowing through it, at constant temperature. Mathematically: V = IR, where R is resistance in ohms. Rearranged forms: I = V/R (current) and R = V/I (resistance). It is the most important formula in CBSE Class 10 Chapter 12.

How is equivalent resistance calculated for resistors connected in parallel?

For resistors in parallel: 1/Req = 1/R₁ + 1/R₂ + 1/R₃. For n identical resistors each of value R: Req = R/n. The equivalent resistance in a parallel combination is always less than the smallest individual resistance — a key fact CBSE examiners frequently test in MCQs and short-answer questions.

Why are household appliances connected in parallel and not in series?

Household appliances are connected in parallel because: (1) each receives the full 230 V supply and operates at rated power, (2) each can be switched on or off independently, and (3) a fault in one appliance does not affect others. In a series circuit, voltage is divided, all devices must run together, and one failure breaks the whole circuit.

What is the function of a fuse in domestic electric circuits?

A fuse protects domestic circuits from overloading and short circuits. If the current exceeds the fuse rating, the fuse wire melts due to excess heat and safely breaks the circuit before wiring or appliances are damaged. Standard fuse ratings in Indian homes are 2 A, 5 A, 15 A, and 32 A. The fuse is always connected in series with the circuit.

What happens to resistance when a wire is stretched to double its length?

Resistance becomes 4 times the original (4R). When the wire is stretched to double its length at constant volume, the cross-sectional area halves. Since R = ρL/A: R′ = ρ(2L)/(A/2) = 4ρL/A = 4R. The general rule: stretch to n× the length → resistance becomes n²× the original. (n = 2 → 4R; n = 3 → 9R). This is a classic CBSE numerical question.

What are the factors that affect the resistance of a conductor?

Resistance depends on four factors: (1) Length (L) — R increases proportionally with length; (2) Cross-sectional area (A) — R decreases as area increases; (3) Material (ρ) — different materials have different resistivities; (4) Temperature — for most conductors, R increases with temperature (Ohm's Law is valid only at constant temperature).

CBSE board exam tips — Chapter 12 Electricity

  • Parallel vs series quick rule: Parallel Req is always LESS than the smallest R; series Req is always MORE than the largest R.
  • Stretched wire trap: Stretch to n× length → R becomes n²R, NOT n×R. The most common wrong answer in CBSE numericals.
  • Fuse is in series; appliances are in parallel. Many students get this reversed. The fuse must be in series to break the circuit.
  • Ohm's Law has limits: V = IR holds only at constant temperature. Diodes, LEDs, and filament bulbs do NOT obey Ohm's Law (non-ohmic conductors).
  • Power numericals: Use P = V²/R when V and R are given; use I = P/V to find the fuse current for an appliance.
  • Assertion–Reason (new pattern since 2023): Both A and R can be true but R may not be the correct explanation for A — read both statements carefully.

More Class 10 Physics MCQ quizzes

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Saurabh Kumar
CBSE & Bihar Board educator | Physics, Chemistry, Biology, Maths | Founder of AceTheGrade

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