Question

If a graph is plotted with atomic number on x-axis and square root of frequency of a spectral line of characteristic x-rays on the y-axis, then it will be

• A. A straight line passing through the origin
• B. A parabola
• C. A straight line not passing through the origin
• D. A rectangular hyperbola

Answer 1

The correct option is C A straight line not passing through the origin

Moseley's Law describes the relationship between atomic number and frequency of a spectral line of characteristic X-rays. When the square root of the frequencies of the characteristic X-rays from the elements is plotted against the atomic number, a straight line is obtained following the equation:
$\sqrt{\nu }=a(Z-b)$. So, this will never touch the origin.
So, the answer is option (C).