CBSE Class 12 Physics – Current Electricity

Previous Chapter Next Chapter

Study Materials

12th

12th - Physics

Current Electricity

Chapter Overview

This chapter focuses on the behavior of electric charges in motion. You’ll study electric current, current density, drift velocity, Ohm’s law, resistance, resistivity, temperature dependence, internal resistance, Kirchhoff’s laws, measurement devices, and electrical power. These concepts explain how real-world circuits and electrical systems work.

Important Keywords

  • Electric Current (I): Amount of charge per unit time (I = ΔQ/Δt; unit: Ampere).
  • Current Density (J): Current per unit area (vector quantity, J = I/A).
  • Drift Velocity (vₙ): Average velocity of charge carriers under electric field.
  • Resistivity (ρ): Intrinsic property of a material (R = ρl/A).
  • Ohm’s Law: V = IR; J = σE where σ = 1/ρ. :contentReference[oaicite:0]{index=0}
  • Internal Resistance (r): Resistance within a cell or battery.
  • Kirchhoff’s Laws: Junction rule (∑I = 0) and loop rule (∑V = 0). :contentReference[oaicite:1]{index=1}
  • Electrical Power (P): P = VI = I²R = V²/R.
  • Potentiometer: Instrument for precise emf measurement without drawing current.

Detailed Notes

to view full chapter (Current Electricity - Detailed Notes) resources.