JEE Main 2019 Physics question

PhysicsMoving Charges and MagnetismJEE Main 2019

A proton, an electron, and a helium nucleus, have the same energy. They are in circular orbits in a plane due to magnetic field perpendicular to the plane. Let , and be their respective radii, then,

Answer: (C)

Solution

: , and .

Question ID VK-009856