UNIT − 2 CURRENT DAY 6:
Ohm’s law Resistance and its effects
BASIC CONCEPTS of
Current and its Unit
Drift velocity
Relaxation Time
Mean free path
Mobility
Current density
Existence of electric field inside conductor
Ohm Law
limitations 3.6 and 3.7
Ohmic Conductor and Non Ohmic conductor
Temperature dependence
Constantan Eureka and Manganin
Temperature coefficient of resistance
3.9, 3.10 and 3.11
Fuse, Standard resistance and Heater Wire
Colour coding
Power, and energy
Resistances Series and Parallel
Internal Resistance
Cells in series and parallel
Kirchhoff law
Wheat stone Bridge
Slide wire of Meter Bridge
Potentiometer
- Define drift velocity and derive an expression for it.
- Derive the expression I=nAevd
- Deduce Ohm’s law from elementary ideas and hence write an expression for resistance and resistivity.
- Derive an expression for conductivity in terms of mobility
- Explain the color coding of carbon resistors.
- Derive an expression for the current in a circuit with external resistance R when (a) n identical cells of emf E and internal resistance r are connected in series (b) m identical cells are connected in parallel
- State and explain Kirchhoff’s laws.
NCERT CHAPTER