Question

In X-ray spectrum wavelength $\lambda$ of line $K_a$ depends on atomic number $Z$ as

• A. $\lambda \propto Z^2$
• B. $\lambda \propto (Z-1{)}^2$
• C. $\lambda \propto \frac{1}{(Z-1)}$
• D. $\lambda \propto {\frac{1}{(Z-1)}}^2$

Answer 1

Answer: (D)

$\lambda \propto {\frac{1}{(Z-1)}}^2$

As we know,

$f\propto (z-1{)}^2$

so,

$\lambda \propto \frac{1}{(z-1{)}^2}$