Question

The two lines A and B in fig. shoe the phot of de Broglie wavelength `(lamda)` as a function of `(1)/(sqrtV) `(V is the accelerating potential) for teo particles having the same charge. Which of the two represents the particle of heavier mass?

Answer 1

In terms of accelerating potential V, the de Broglie wavelength of a charged particle is given by
`lamda=(h)/(sqrt(2meV))` …(i)
Where e is charge and m is mass of the particle. Equation (i) represents a straight line, whose slope is `(h)/(sqrt(2me))`. The slope of the line is inversely proportional to `sqrtm`. since the slope of line A is lesser, it represents the particle of heavier mass