Q.
A proton and a deuteron both having the same kinetic energy, enter perpendicularly into a uniform magnetic field B. For motion of proton and deuteron on circular path of radius rP and rd respectively, the correct statement is
Radius of circular path r=qBmv...(i)
and kinetic energy KE=21mv2
or v=m2KE
putting the value of v in Eq. (i) r=qBmm2KE=qB2mKE… (ii)
For proton (1H1) and deuteron (1H2)
electronic charge are same and both have same kinetic energy. ∴ By Eq. (ii) r∝m
or rprd=mpmd ∵md=2mp ∴rprd=mp2mp ⇒rd=2rp