A particle with electric charge e moves in a magnetic field B =- r / r^3 with velocity v . Here is a non-zero constant and r r =r^2 . Select the correct statement(s).

Options

1. AAngular momentum L =m r v is a constant of motion.
2. BVector J =m r v +e r / r is a constant of motion.
3. CKinetic energy of the particle is constant.
4. DTotal flux of the magnetic field through a sphere centered at the origin is a non-zero constant.