An element of atomic number 9 emits `K_(alpha)` X-ray of wavelength `lamda`. Find the atomic number of the element which emits `K_(alpha)` X-ray of wavelength `4lamda`.

An element of atomic number 9 emits `K_(alpha)` X-ray of wavelength `l

1.	An element of atomic number 9 emits `K_(alpha)` X-ray of wavelength `lamda`. Find the atomic number of the element which emits `K_(alpha)` X-ray of wavelength `4lamda`.
Answer» For `K_(alpha)` X-ray, `(Z-1)^2lamda=`constant. Hence, `(9-1)^2lamda=(Z-1)^2(4lamda)` `(Z-1)^2=(64)/(4)=16` `Z-1=4` or `Z=5`

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An element of atomic number 9 emits `K_(alpha)` X-ray of wavelength `lamda`. Find the atomic number of the element which emits `K_(alpha)` X-ray of wavelength `4lamda`.

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