An electron travelling in the same direction that an electric field points initially has a speed of 4.21 ×107 meters per second. If the electric field has a magnitude of 2.28 ×104 N/C, how far does the electron travel before stopping?

Answer 1

m•a=F =e•E,
a =e•E/m,
s =v²/2•a = v²•m/2e•E =
=4.21•10^7)²•9.1•10^-31/2•1.6•10^-19•2.28•10^4 = 0.22 m.