When a proton moves at a speed vvv perpendicular to a uniform magnetic field of flux density BBB, the radius of its circular path is RRR.
A second proton moves at a speed 3v3v3v perpendicular to a uniform magnetic field of flux density 2B2B2B.
What is the radius of the path of the second proton?
23R\frac{2}{3}R32R
32R\frac{3}{2}R23R
6R6R6R
16R\frac{1}{6}R61R