A proton is initially moving at 3.0 x 105 m/s. It moves 3.5 m in the direction of a uniform electric field of magnitude 120 N/C. What is the kinetic energy of the proton at the end of the motion

The kinetic energy is  

Explanation:

From the question we are told that

    The initial speed of the proton is  

    The distance covered is  

   The magnitude of the electric field is

Generally the mass of  a proton is  

and the charge on a proton is  

  Now according to work energy theorem,

=>    

=>    

Where   is final kinetic energy and  is initial kinetic energy which is  mathematically represented as

Now the net workdone(W) is mathematically represented as

So

substituting values

force is mass*acceleration.

we have a very small mass: 11.4*0.001 kg

if we want 0.035n of force, we need an acceleration:

0.035 = 11.4*0.001*a

a = 0.035/(11.4*0.001) m/s^2