Splitting of spectral lines when atoms are subjected to a strong electric field is called:

The kinetic energy of photoelectrons depends on ...............

$\alpha$-rays have

If light waves pass through a $Nicol$ prism,then all the oscillations occur only in one plane. Such a beam of light is called:

It is observed that characteristic $X$-ray spectra of elements show regularity. When frequency to the power '$n$' i.e.,$v^{n}$ of $X$-rays emitted is plotted against atomic number '$Z$',the following graph is obtained. The value of '$n$' is

Given below are two statements about $X$-ray spectra of elements :
Statement $(I) :$ $A$ plot of $\sqrt{\nu}$ ($\nu =$ frequency of $X$-rays emitted) vs atomic mass is a straight line.
Statement $(II) :$ $A$ plot of $\nu$ ($\nu =$ frequency of $X$-rays emitted) vs atomic number is a straight line.
In the light of the above statements choose the correct answer from the options given below :