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Question
Solve the numerical problem.
Calculate the wavelength in nm of an X-ray wave of frequency 2.0 × 1018 Hz.
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Solution
Given: c = 3 × 108 , ν = 2 × 1018 Hz
To find: Wavelength (λ)
Formula: c = νλ
Calculation: From formula,
λ = `"c"/ν=(3xx10^8)/(2xx10^18)` = 1.5 × 10−10 = 0.15 nm
The wavelength of an X-ray is 0.15 nm.
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