Question

A proton Nd a alpha particles enter in the same magnetic field perpendicularly with same kinetic energy .find the ratio of there radii

Answer 1

Answer:

q v B = Q V B    the magnetic force on the particles

v = 2 V    since the charge on the alpha particle is twice that of the proton

q v B = m v^2 / r or  q B =   m v  / r   small letters - proton,   cap letters alpha

                                             using small letters for proton and caps for alpha

q r B = m v   and Q R B = M V

(q / Q) * (r / R) = (m / M) * (v / V)     dividing equations

1/2 * (r / R) = 1/4 (v / V)    since Q = 2 q    and M = 4 m

r / R = 1/2 ( v / V)

Since m v^2 = M V^2     v^2 / V^2 = M / m  = 4

then v / V = 2

So r / R = 1     their radii are equal

Answer 2

Answer:

this is the required answer