ELECTRIC CHARGES AND FIELDS
Charging by friction
CHARGING
Charging by induction
Rubbing two charged bodies may either repel or attract each other
+ve & -ve
polarity of charges
Inducing a charged rod to a neutral sphere will alter the +ve & -ve charge according to the polarity of rod induced
Basic Properties of Charges
Conservation of Charges
Quantization of Charges
Additivity of Charges
Charges are algebraically added if 'n' no charges are present in a system
Earthing/Grounding
The total charge of an isolated system is always a constant
Charges are not continuous. They are an integral multiple of e
Coulombs Law
The force between two point charges is directly proportional to the product of their magnitude and inversely proportional to the sq. of their distance
The amount of charge placed at a distance of 1m from an identical charge experience a force of 9x10^9 N
1 Coulomb
Electric Field
It is the region around a source charge where its forces are felt
Electric dipole
Pair of equal & opp. point charges separated by distance 2a
Axial point
Equitorial point
Torque on dipole
Electric flux
Total number of electric field lines passing normally to a given area
F=(K Qq)/r^2
]
It is a scalar quantity
Guass's law
Total flux through a closed surface is 1/8.85x10^-12
proof
Applications
Area vector
