A point charge +Q is placed at point O as shown in the figure. Is the potential difference – positive, negative or zero ?
A point charge Q is placed at point ‘O’ as shown in figure. Is the potential at point A, i.e., , greater, smaller or equal to potential, at point B, when Q is (i) positive, and (ii) negative charge?
Define capacitive reactance. Write its S.I. unit.
Does the charge given to a metallic sphere depend on whether it is hollow or solid?
Figure shows the field lines due to a positive charge. Is the work done by the field in moving a small positive charge from Q to P, positive or negative? Give reason.
For any charge configuration, equipotential surface through a point is normal to the electric field. Justify.
State which of the two a capacitor or an inductor, tends to become SHORT when the frequency of the applied alternating voltage has a high value.
What is the geometrical shape of equipotential surfaces due to an isolated charge ?
Why are electric field lines perpendicular at a point on an equipotential surface of a conductor ?
Why is choke coil needed in the use of fluorescent tubes with ac mains ?
Why is the use of ac voltage preferred over dc voltage ? Give two reasons.
Why must electrostatic field at the surface of a charged conductor be normal to the surface at every point ? Give reason.
A capacitor of 4 μF is connected as shown in the circuit Figure. The internal resistance of the battery is 0.5 Ω. The amount of charge on the capacitor plates will be :
In a series LR circuit = R and power factor of the circuit is P₁. When capacitor with capacitance C such that = is put in series, the power factor becomes P₂. Calculate P₁ / P₂.
Define ‘Wattless current’.