Diamagnetic material susceptibility χ is: MCQ with Answer and Explanation

Explanation:
At resonance frequency ω₀ = 1/√(LC), inductive reactance X_L = ωL equals capacitive reactance X_C = 1/(ωC), so they cancel. Impedance Z = √[R² + (X_L - X_C)²] = R, which is minimum (since R is the only remaining component). Current is maximum at resonance. Memory tip: 'LCR resonance: Z_min = R, I_max, purely resistive'. This AC circuit concept is frequently tested in competitive exams. Always distinguish series resonance (Z min) from parallel resonance (Z max) behavior.

Explanation:
R ∝ 1/A.

Explanation:
Iris adjusts pupil size. In bright light pupil constricts, dim light dilates. Retina forms image. Cornea and lens focus. Eye is like camera.