CBSE Class 12 Physics Electrostatics Notes Set A

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• Properties of electric field lines:

♦ Arbitrarily starts from +ve charge and end at –ve charge

♦ Continuous, but never form closed loops

♦ Never intersect

♦ Relative closeness of the field lines represents the magnitude of the field strength.

♦ For a set of two like charges – lateral pressure in between

♦ For a set of two unlike charges – longitudinal contraction in between.

♦ Electrostatic Potential: Work done per unit positive Test charge to move it from infinity to that point in an electric field. It is a scalar. SI unit: J/C or V
V = W / qo

•  Electrostatics of conductors

(i) Inside a conductor Electrostatic field is zero

(ii) On the surface E is always Normal

(iii) No charge inside the conductor but gets distributed on the surface

(iv) Charge distribution on the surface is uniform if the surface is smooth

(v) Charge distribution is inversely proportional to ‘r’ if the surface is uneven

(vi) Potential is constant inside and on the surface

♦ Equipotential surfaces: The surfaces on which the potential is same everywhere.

♦ Work done in moving a charge over a equipotential surfaces is zero.

♦ No two equipotential surfaces intersect.

♦ Electric field lines are always perpendicular to the equipotential surfaces.

♦ Equipotential surfaces: The surfaces on which the potential is same everywhere.

♦ Work done in moving a charge over a equipotential surfaces is zero.

♦ No two equipotential surfaces intersect.

♦ Electric field lines are always perpendicular to the equipotential surfaces

Please refer to attached file for CBSE Class 12 Physics Electrostatics.