Question

Choose the
A uniform electric field Eis created between two,
parallel charged plates as shown in figure. An
electron enters the field symmetrically between the
plates with a speed vo The length of each plate is
The angle of deviation (0) of the path as it comes
out of the field is​

Answer 1

Answer:

tan

−1

mv

0

2

eEl

Explanation:

Correct option is

C

tan

−1

mv

0

2

eEl

Since, no field and hence no force act on the electron along X-direction.

Hence, v

x

remains constant.

Hence, time taken=t=

v

x

l

=

v

o

l

And force on electron is F=qE=eE along y-direction.

Acceleration of electron =a=

m

F

=

m

eE

along Y-direction

Initial velocity-

u

x

=v

o

and u

y

=0

Final velocity while getting out -

V−x=v

o

v

y

=u

y

+at=

mV

o

eEl

Now, angle is given by-

tanθ=

v

x

v

y

=

mv

o

2

eEl

⟹θ=tan

−1

mv

o

2

eEl

Answer-(C)