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3 years ago

Find the wavelength of the balmer series spectral line corresponding to n = 15.

Physics

1 answer:

Anna71 [15]3 years ago

7 0

Answer:

371.2 mm

Explanation:

The Balmer series of spectral lines is obtained from the formula

1/λ = R(1/2² -1/n²) where λ = wavelength, R = Rydberg's constant = 1.097 × 10⁷ m⁻¹

when n = 15

1/λ = 1.097 × 10⁷ m⁻¹(1/2² -1/15²)

= 1.097 × 10⁷ m⁻¹(1/4 -1/225)

= 1.097 × 10⁷ m⁻¹(0.25 - 0.0044)

= 1.097 × 10⁷ m⁻¹ 0.245556

= 2.693 10⁶ m⁻¹

So,

λ = 1/2.693 10⁶ m⁻¹

= 0.3712 10⁻⁶ m

= 371.2 mm

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