Given below are two statements about X-ray spectra of elements : Statement (I) : A plot of $$\sqrt{v}$$($$\upsilon$$ = frequency of -rays emitted) vs atomic mass is a straight line. Statement (II) : A plot of $$\upsilon(\upsilon$$ = frequency of -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 :

Evaluate two statements about X-ray spectra (Moseley's law).

Moseley's law: $$\sqrt{\nu} = a(Z - b)$$, where Z is atomic number, and a, b are constants.

Statement I: A plot of $$\sqrt{\nu}$$ vs atomic mass is a straight line.

Moseley's law relates $$\sqrt{\nu}$$ to atomic number Z, not atomic mass. Since atomic mass and Z don't have a perfectly linear relationship, this is FALSE.

Statement II: A plot of $$\nu$$ vs atomic number is a straight line.

From Moseley's law: $$\sqrt{\nu} = a(Z-b)$$, so $$\nu = a^2(Z-b)^2$$. This is a parabolic (quadratic) relationship, not linear. So this is FALSE.

The correct answer is Option 3: Both Statement I and Statement II are false.