Help with electron in electric field problem

[Nano]

Homework Statement

An electron has an initial velocity of 5 ×
105 m/s in the x direction. It enters a uni-
form electric field ~E = (440 N/C) ˆj which is
in the y direction.
The charge and mass of an electron are
1.6×10−19 C and 9.11×10−31 kg, respectively.
Find the acceleration of the electron.
Answer in units of m/s2.

Homework Equations

F=eq
F=ma

The Attempt at a Solution

I tried using those two equations and coming up with a = Eq/m, but that's not the correct answer!

 

[Doc Al]

I tried using those two equations and coming up with a = Eq/m, but that's not the correct answer!

That should work just fine. Show what you did.

Since acceleration is a vector, they may want you to specify its direction as well.

 

[Nano]

440 * (1.6e-19)/ (9.11e-31) = 7.2777e13 m/s^2

I'm submitting it into an electronic homework service, which is very picky. I tried submitting a negative answer too, but that's is not correct either...

 

[Doc Al]

440 * (1.6e-19)/ (9.11e-31) = 7.2777e13 m/s^2

Check your arithmetic. (I suspect it's just a typo here.)

I'm submitting it into an electronic homework service, which is very picky. I tried submitting a negative answer too, but that's is not correct either

Since the directions were given using unit vectors, perhaps that's what they want in the answer.

 

[Nano]

Check your arithmetic. (I suspect it's just a typo here.)

Aha! Thank you!