Current Electricity — Class 12 Physics NCERT Solutions (Free)
Free step-by-step NCERT solutions for Class 12 Physics chapter "Current Electricity" — 8 important questions with detailed answers for CBSE board exam preparation.
TL;DR: Free step-by-step NCERT solutions for Class 12 Physics chapter "Current Electricity" — 8 important questions with detailed answers for CBSE board exam…
By Syllab.in · Updated
Key Questions Covered:
- Define electric current. State its SI unit and symbol.
- State Ohm's law. A wire has resistance 5 Ω. If potential difference across it…
- Define resistance and resistivity. Write formula relating resistance to resis…
- + 5 more questions in the full chapter
Solutions Summary:
| Question | Status |
|---|---|
| Define electric current. State its SI unit and symbol. | ✓ Solved |
| State Ohm's law. A wire has resistance 5 Ω. If potential … | ✓ Solved |
| Define resistance and resistivity. Write formula relating… | ✓ Solved |
Showing 3 of 8 questions
Q1: Define electric current. State its SI unit and symbol.
Electric Current (I): Rate of flow of electric charge through a conductor.
I = Q/t (charge per unit time)
SI Unit: Ampere (A) = Coulomb per second (C/s)
Symbol: I
Direction: Conventional current flows from positive to negative terminal (opposite to electron flow).
One Ampere: When charge of 1 co...
Q2: State Ohm's law. A wire has resistance 5 Ω. If potential difference across it is 10 V, find the current.
Ohm's Law: At constant temperature, current through conductor is directly proportional to applied potential difference.
I ∝ V (at constant temperature)
V = IR
or I = V/R
where V = potential difference (V)
I = current (A)
R = resistance (Ω)
Given: R = 5 Ω, V = 10 V
Step 1: I = V/R = 10/5
Step 2:...
Q3: Define resistance and resistivity. Write formula relating resistance to resistivity.
Resistance (R): Opposition offered by conductor to flow of electric current.
R = V/I (potential difference per unit current)
SI Unit: Ohm (Ω) = V/A
Resistivity (ρ): Inherent property of material that opposes current flow.
SI Unit: Ohm-meter (Ω⋅m)
Symbol: ρ (rho)
Relation between R and ρ:
R = ρL...
Showing 3 of 8 questions. Visit the full page for complete solutions.