A proton and an α -particle, having kinetic energies K _ p and K _...

$r = \dfrac{mv}{qB} = \dfrac{p}{qB}\dfrac{{m}_{\alpha}}{{m}_{p}} = 4$

$\dfrac{{r}_{p}}{{r}_{\alpha}} = \dfrac{{p}_{p}}{{q}_{p}}\dfrac{{q}_{\alpha}}{{p}_{\alpha}} = \dfrac{2}{1}$

$\dfrac{{p}_{p}}{{p}_{a}} = \dfrac{2{q}_{p}}{{q}_{a}} = 2\left(\dfrac{1}{2}\right)$

$\dfrac{{p}_{p}}{{p}_{\alpha}} = 1$

$\dfrac{{K}_{p}}{{K}_{\alpha}} = {p}_{p}^{2}{p}_{\alpha}^{p}\dfrac{{m}_{\alpha}}{{m}_{p}} = \left(1\right)\left(4\right)$