Time taken by proton to complete one complete circular orbit= 7.28 x 10⁻⁸ s
Explanation:
For proton, the centripetal force required for circular motion is provided by the magnetic force,
so Fm= Fc
q v B = m v²/r
m= mass of charged particle
v= velocity
B =magnetic field
q= charge
r= radius of circular path
v= q B r/m
now v= r ω
ω= angular velocity
ω r = q B r /m
ω=q B /m
now ω= 2π/T where T =time period
so 2π/T=q B/m
T= 2 πm/q B
T= 2π (1.67 x 10⁻²⁷)/ [( 1.6 x 10⁻¹⁹)* (0.9)]
T= 7.28 x 10⁻⁸ s