The ratio of moment of an electron and an `alpha`-particle which are accelerated from rest by a potential difference of `100V` is

Options

A. 1
B. `sqrt(2 m_e)/(m_alpha)`
C. `sqrt(2m_e)/(m_alpha)`
D. `sqrt( m_e)/(2m_alpha)`

Answer

D

Explanation

Momentum p = mv and v = `sqrt(2QV)/m`
`implies`p = `sqrt (2QmV) implies p alpha sqrt(Qm)`
`implies` `(p_e)/(P_alpha) = sqrt((e xx m_e)/(2exx m_a)) = sqrt ((m_e)/(2m_alpha))`