Govt. Exams
V ∝ 1/r. When distance increases 4 times (2 m to 8 m), potential decreases 4 times: 100/4 = 25 V
When identical conducting spheres touch, charge distributes equally. Total charge = Q - Q = 0. Each sphere gets 0 charge.
Electric dipole moment p = q × d, where q is charge in Coulombs and d is distance in meters. Unit = C·m
In parallel: same voltage V. Q₁ = C₁V, Q₂ = C₂V. Therefore Q₁/Q₂ = C₁/C₂.
By Gauss's law: Φ = Q/ε₀ = (5 × 10⁻⁶)/(8.85 × 10⁻¹²) ≈ 5.65 × 10⁵ N·m²/C
When identical conductors touch, charge redistributes equally. Total charge = Q + (-Q) = 0, so each gets 0 charge.
The capacitance of a parallel plate capacitor with dielectric is C = Kε₀A/d, where K is the dielectric constant.
Inside and on the surface of a conductor in electrostatic equilibrium, the potential is constant everywhere.
Energy stored in a capacitor is U = (1/2)CV² = (1/2)QV = Q²/(2C).
The capacitance of an isolated conducting sphere is C = 4πε₀R = R/k, where k = 1/(4πε₀).
