question_answer

Two lines A and B in the figure shows the variation of de-Broglie wavelength \[\lambda \]  versus \[1/\sqrt{V},\] where V is the accelerating potential difference, for two particles carrying the same charge. Which one of the two represents a particle of smaller mass?

 

Answer:

            As, \[\lambda =h/\sqrt{2mqV}.\] The slope of \[\lambda \] versus \[1/\sqrt{V}\] graph will be inversely proportional to the square root of mass of the particles. Now, slope of B is greater. Thus line B represents smaller mass.