Absorption of $X$-rays is maximum in which of the following different sheets?

For continuous $X-$rays,the minimum wavelength produced is:

Moseley's law for characteristic $X$-rays is given by $\sqrt{f} = a(Z - b)$. Choose the correct statement.

$X$-rays and $\gamma$-rays of the same energies may be distinguished by

$X$-rays do not undergo diffraction because of their .....

$\Delta \lambda$ is the difference between the wavelength of the $K_\alpha$ line and the minimum wavelength of the continuous $X$-ray spectrum when the $X$-ray tube is operated at a voltage $V$. If the operating voltage is changed to $V / 3$,then the above difference is $\Delta \lambda^{\prime}$. Then: