In this tutorial we are going to learn about WHAT IS RESISTOR & ITS FUNCTION
RESISTOR: Resistance is property of resistor; It opposes the current by doing so it converts electric energy to heat energy
R =ρl/a l – Length
a – Area
ρ – Resistivity of material in ΩM
Conductor – Low Resistivity
Semiconductor – Medium Resistivity
Inductor – High Resistivity
Super Conductor = ρ = 0
Eg. Mercury at 4.15K temp
Rt = R0 (1+ αt )
R0 = Resistance of material at 0°C
α = Temp. Coefficient
t = Change in temp.
WHAT IS OHM’S LAW
- OHM’S LAW states that at constant temp. Current density is directly proportional to field intensity.
- At constant temp, potential difference across Element is directly proportional to current flowing through elements
- OHM’S LAW valid only when Conductivity and temp is constant .