Question
The figure shows a region of length ‘l’ with a
uniform magnetic field of 0.3 T in it and a
proton entering the region with velocity 4 $ \times $ 105
ms–1 making an angle 60o with the field. If the
proton completes 10 revolution by the time it
cross the region shown, ‘l’ is close to
(mass of
proton = 1.67 $ \times $ 10–27 kg, charge of the proton =
1.6 $ \times $ 10–19 C)
