What element has a K α , X-ray line of wavelength 1 . 785 A o ? R = 109737 cm - 1

Given that, Wavelength, λ = 1 . 785 A ∘ = 1 . 785 × 10 - 8 cm Expression for wavelength for k α line 1 λ k α = R Z − 1 2 1 1 2 − 1 2 2 where Z is atomic number. Z − 1 2 = 4 3 1 λ k α 1 R ⇒ Z − 1 2 = 4 3 × 1 1 .785 × 10 − 8 × 1 109737 ⇒ Z − 1 2 = 680 .6 ⇒ Z − 1 = 26 ⇒ Z = 27 Thus, the element is Cobalt.

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ISC Physics Class 12, Part-2>Chapter 12 - X-Rays>QUESTIONS>Q 8

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Find the maximum frequency of X-rays emitted from an X-ray tube operated at $10 kV$ . What will be the energy of the maximum-frequency X-ray photon?

Important Questions on X-Rays

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ISC Physics Class 12, Part-2>Chapter 12 - X-Rays>QUESTIONS>Q 9

What element has a

K_{α}

, X-ray line of wavelength

1.785 \overset{o}{A}

?

R = 109737 {cm}^{- 1}

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ISC Physics Class 12, Part-2>Chapter 12 - X-Rays>For DIFFERENT COMPETITIVE EXAMINATIONS>Q 1

Electrons with de-Broglie wavelength

λ

fall on the target in an X-ray tube. The cut-off wavelength of the emitted X-ray is:

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ISC Physics Class 12, Part-2>Chapter 12 - X-Rays>For DIFFERENT COMPETITIVE EXAMINATIONS>Q 2

The intensity $I$ of X-rays from the Coolidge tube is plotted against wavelength $λ$ , as shown in the figure. The minimum wavelength found is $λ_{C}$ and the wavelength of the $K_{α}$ line is $λ_{K}$ . As the accelerating voltage is increased:

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