A proton and helium nucleus are shot into a magnetic field at right angles to the field with same kinetic energy. Then the ratio of their radii is

Step-by-step solution

The radius of the circular path, of a charges particle in magnetic field r= m v q B = 2 m E q B Here, kinetic energy for proton and helium is same and both are moving in the same magnetic field r m q So, r_ P r_ He = m_ P q_ P m_ He q_ He = m_ P m_ He q_ He q_ P = m 4 m 2 q q = 1 1