please help, i don't understand this. topic: electric charge, force, and field strength?

Question

A proton accelerates from rest in a uniform electric field of 650 N/C. At some time later, its speed is 1.30 106 m/s.

a) What is the magnitude of the acceleration of the proton?
_________m/s2 (units)
(b) How long does it take the proton to reach this speed?
_________seconds
(c) How far has it moved in this time interval?
_________meters
(d) What is its kinetic energy at the later time?
__________ Joules



....sorry, i just don't understand how to go about these problems. if you could explain your answer that'd be great too!!!

Answer 1

You know that the force applied to your proton is 650 N/C. Look up the charge on one proton in Coulombs. Then multiply times 650 N/C to find out how many Newtons of force are being applied. You are probably familiar with the equation F=ma or Force = Mass times Acceleration. Now that you know the Force, you can look up the Mass of a proton and then solve for the accleration. Let's call the acceleration "a". The acceleration is the rate of change of the velocity. The acceleration in this problem is constant. So we don't have to deal with derivatives or integrals just yet. We know that the constant acceleration a times the time elapsed t gives us V, the velocity. We know the velocity that we are interested in and we have found a. So solve the eqation for t. a*t=V becomes t = V/a. That is the answer to part b. How far has it moved? Now we have to integrate Velocity over that time interval. V = a*t. The position X = integral of V *dt from 0 to 1.30 106. Integral of Vdt = a*t^2/2 Plug in t and solve for the distance. Now look up the equation for Kinetic Energy, plug in your values and solve.

Answer 2

You will need the mass of the proton, as well as its charge, to do this, since the force is proportional to charge but the acceleration is inversely proportional to mass. First, use the proton charge to figure the force. Then, use the force in the usual equations, along with the mass, to figure out the other parts of the problem. Finally, compare the proton speed with the speed of light to verify that the speed is small such that relativistic effects can be ignored.

Answer 3

acceleration of proton = force /mass = Chargexfield/mass
= 1.6x10^-19x650/1836x9.1x10^-31

Calculate acceleration and use equations such as v^2 = 2as to calculate s and then use v = at to get t and E = (1/2) mv^2 to get kinetic energy

Answer 4

ask your teacher to help you understang it.