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प्रश्न
The wavelength of X-rays is 0.01 Å. Calculate its frequency. State the assumption made, if any.
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उत्तर
1. Wavelength of X-rays: λ = 0.01Å
= `1/100 xx 10^-10` m
λ = 10-12 m
2. Assumption made is speed of X-rays = Speed of light = 3 × 108 m
C = f λ
f = `C/ λ`
= `(3 xx 10^8)/(10^-12)`
= `3 xx 10^(8+12)`
f = 3 × 1020 Hz
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