Question

what is the wavelength of the x-ray emitted from a tungsten target (Z=74) when an electron moves from the M-shell (n=3) to the K-shell(n=1)

Answer 1

$$\frac{1}{\lambda}=R(Z-1)^2\left(\frac{1}{1^2}-\frac{1}{3^2}\right)$$

$$\frac{1}{\lambda}=1.097\cdot10^7(74-1)^2\left(\frac{1}{1^2}-\frac{1}{3^2}\right)$$

$$\lambda=1.9\cdot10^{-11}\ m$$