The device used to convert DC to AC is MCQ with Answer and Explanation

Explanation:
Charge of electron e = 1.6 × 10⁻¹⁹ C. Number n = 1/e = 1/(1.6×10⁻¹⁹) = 6.25 × 10¹⁸. This is a huge number. Important for current (1 A = 1 C/s).

Explanation:
For parallel combination: 1/R_eq = 1/R₁ + 1/R₂ + 1/R₃ = 1/2 + 1/3 + 1/6 = (3+2+1)/6 = 6/6 = 1. Thus R_eq = 1Ω. Note: Equivalent resistance in parallel is always less than the smallest individual resistance (here 2Ω). Memory tip: 'Parallel: reciprocal sum; result < min(R)'. This standard calculation tests parallel resistance formula application, frequently appearing in competitive exams. Always simplify fractions carefully; common denominator method avoids errors. Verify: 1Ω < 2Ω, consistent with parallel behavior.

Explanation:
Dispersion is splitting of light into constituent colours due to variation of refractive index with wavelength. Violet deviates most, red least. Prism doesn't absorb but disperses. Rainbow formation is due to dispersion, refraction, reflection in water droplets.