Practice question

Given: What is the orbital period of an electron in the n = 4 orbit if v_1 = 2.2 × 10⁶m/s and r_1 = 5.3 × 10⁻¹¹m ? Formula: v_4 = 2.2 × 10⁶/4 = 5.5 × 10⁵m/s. Substitution & Calculation: r_4 = 16 × 5.3 × 10⁻¹¹= 8.48 × 10⁻¹⁰m . T = 2π r_4/v_4 = frac2 × 3.14 × 8.48 × 10⁻¹⁰⁵.5 × 10⁵approx 9.68 × 10⁻¹⁵s . Final Result: The computed value matches expected outcome and confirms correct choice as per latest NCERT 2026-27.