The radius of and `alpha`-particle moving in a circle in a constant magnetic field is half of the radius of and electron moving in circular path in the same field. The de Broglie wavelength of `alpha`-particle is n times that of the electron. Find n (an integer).

Answer

A

Explanation

`r_(alpha)=1/2r_(e)rArr P_(alpha)/(Bq_(alpha))=1/2P_(e)/(Bq_(e))rArr P_(alpha)/(2e)=1/2xxP_(e)/e rArrP_(alpha)=P_(e)`
de-Broglie's wavelength `lambda=h/p rArr lambda_(alpha)=lambda_(e)`