If 'R' is the radius of dees and 'B' be the magnetic field of induction which positive charges (q) of mass (m) escapes from the cyclotron, then its maximum speed `(V_(max))` is

Options

A. `(qR)/(Bm)`
B. `(qm)/(BR)`
C. `(qBR)/m`
D. `m/(qBR)`

Answer

C

Explanation

For the cyclotron, the centripetal force `(mv^(2))/r` is provided by the magnetic force `qvB`. When the positive charges escape from the cyclotron, they have maximum speed `V_(max)` and maximum radius R. `therefore (mV^(2)_(max))/R=qV_(max)B therefore V_(max)=(aBR)/m`.