-- You've GOT the kinetic energy of the bullet.
-- That's the amount of work that has to be done to stop it.
-- work = (avg force) x (penetration) and they just gave you the average force.
-- Did you think it would be this easy ?
On a roller coaster, the greatest potential energy is at the highest point of the roller coaster
Explanation:
Given that,
Two particles, an electron and a proton, are initially at rest in a uniform electric field of magnitude 570 N/C.
We need to find their speeds after 47.6 ns.
For electron,
The electric force is given by :
Let a be the acceleration of the electron. So,
F = ma
m is mass of electron
Let v be the final velocity of the electron. So,
v = u +at
u = 0 (at rest)
So,
For proton,
Acceleration,
Now final velocity of the proton is given by :
Hence, this is the required solution.