acceleration of an electron

[3.14159265358979]

the mass of the electron is 9.1x10^-31 kg and its charge is -1.6x10^-19 c. Calculate the acceleration of an electron that is in a constant electrin field who intensity is 5.10x10^2 N/C upwards. (answer according to back: 9x10^13 m/s^2 (down))

thank you very much.

[Doc Al]

Where are you stuck? (Show your work.)

You'll need to know the definition of electric field and Newton's 2nd law.

[3.14159265358979]

i'm stuck on the acceleration part? how do i get it into the formula?
i know electric field = (kq) / r^2 and F = ma? thanks

[Doc Al]

i know electric field = (kq) / r^2 and F = ma?
That formula is for the electric field of a point charge: you don't need it for this problem. In this problem, the electric field is given. What you do need to know is how much force will that field exert on the electron. The magnitude of the force is given by F = qE.

[3.14159265358979]

yes, of course! thanks i understand know...