Question

A proton and an electron are placed in a uniform electric field.
(a) The electric forces acting on them will be equal.
(b) The magnitudes of the forces will be equal.
(c) Their accelerations will be equal.
(d) The magnitudes of their accelerations will be equal.

Answer 1

Explanation:

answer will be number (d)

Answer 2

(b) is correct.

Explanation:

We know that,

$\vec{F}=q \vec{E}$

The value of q will be the same for an electron and a proton, but the symbol will be the opposite.  

Thus, they will experience a force equal in magnitude but opposite in direction.

Now,

$\vec{F}=q \vec{E}=m \vec{a}$

$\vec{a}=\frac{q \vec{E}}{m}$

As the electron and proton have differing mass m values, they will have different acceleration magnitudes. Sometimes, because of the opposite signs of q they'll vary in direction.