1.

A proton of mass m and accelerated by a potential difference Vgets into a uniform electric field of a parallel plate capacitor parallel to plates of length 1 at mid-point of its separation between plates. The field strength in it varies with time as E = at, where a is a positive constant. Find the angle of deviation of the proton as it comes out of the capacitor. (Assume that it does not collide with any of the plates.)

Answer»


Solution :`v_x=vsqrt(((2qV)/m)), t=1/v_x=lsqrt(m/(2qV))`
`a_y=(qE)/m=(qat)/m=(dv_y)/(DT)`
INTEGRATING both sides we get
`v_y=(qat^2)/(2M)`
`or v_y=((qa)/(2m))l^2(m/(2qV))=(al^2)/(4V)`
Now, ANGLE of deviation
`theta=tan^-1(v_y/v_x)=tan^-1((al^2)/(4V)/sqrt((2qV)/m))`
`=tan^-1((al^2)/(4V) sqrt(m/(2EV)))`


Discussion

No Comment Found

Related InterviewSolutions