Dual Nature of Radiation and Matter question for JEE Main (JEE Main 2021 (24 Feb, Shift 2)), with solution

Answer: (A) 4 : 1

$\lambda = \dfrac{h}{mv}$; equal $\lambda$ means $m_pv_p = m_\alpha v_\alpha$, so $\dfrac{v_p}{v_\alpha} = \dfrac{m_\alpha}{m_p} = \dfrac{4}{1}$.

Solution by Sreeraj P, M.Sc Physics