Practice question

**Quantization of charge** states observable charge is integer multiple of elementary charge e = 1.6×10⁻¹⁹ C, q = n·e, and total charge is conserved in isolated systems. Loss of electrons produces positive charge, and number of transferred electrons follows n = q/e, linking macroscopic charge measurement to microscopic carriers. E = (k |q|/r²) . k = 9 × 10⁹ N·m²/C² , q = 6 × 10⁻⁶ C , r = 3 m . E = 9 × 10⁹ × (6 × 10⁻⁶/(3)²) = 9 × 10⁹ × (6 × 10⁻⁶/9) = 6 × 10³ N/C . Substituting values gives 6 × 10³ N/C, which matches