engineering physics MCQ #597

The ratio of the wavelengths of the first lines of Lyman and Balmer series is

engineering physics MCQ #597

  1. Question 1

    Q1. The ratio of the wavelengths of the first lines of Lyman and Balmer series is

    • A) 1 : 4
    • B) 4 : 27
    • C) 27 : 4
    • D) 1 : 1

    Answer: 4 : 27

    Explanation: Use the Rydberg formula to find λ_Lyman = 1 / (R * (1 - 1/4)) and λ_Balmer = 1 / (R * (1/4 - 1/9)), then λ_Lyman : λ_Balmer = 4/3 : 36/5 = 4/3 * 5/36 = 20/27 * 4/4 = 5/27 * 4 = 20/27.