Two resistors 6 Ω and 3 Ω are connected in parallel. Find equivalent resistance.
Answer framework: Use reciprocal formula to obtain 2 Ω; show units.
All Class 10 Science notes
Chapter 11 • Physics
Electricity
Solve circuit numericals using current, potential difference, resistance, Ohm's law, combinations, heating effect and electrical power.
Core concepts checklist
Electric current and potential difference
Ohm's law and V–I graphs
Resistance and resistivity
Series and parallel resistor combinations
Heating effect, electric power and energy
Formula & fact bank
I = Q/t
V = W/Q
V = IR
R = ρl/A
Rₛ = R₁ + R₂ + …
1/Rₚ = 1/R₁ + 1/R₂ + …
P = VI = I²R = V²/R
H = I²Rt
Diagrams to practise
Draw with pencil, use straight label lines, add arrows and write a precise caption.
- 1Circuit symbols
- 2Ohm's law circuit
- 3Series and parallel networks
- 4V–I graph
CBSE examiner focus
- Convert mA to A and minutes to seconds
- Show formula, substitution, calculation and unit
- Explain why household appliances are connected in parallel
Board-style practice
Derive expressions for electric power and solve an energy-cost case.
Answer framework: Start P = W/t = VQ/t = VI, derive variants using Ohm's law, then convert kWh correctly.
Turn revision into marks with Eduvista
Use this guide for recall, then practise timed answers and get feedback. Eduvista combines visual notes, NCERT clarity, board-pattern tests and personal doubt support.