How Can You Find the Electric Field E with Given Conditions?

[Sanjay101]

1. An electron has an initial velocity of (11.0 j + 16.0 k) km/s and a constant acceleration of (2.00 1012 m/s2) i in a region in which uniform electric and magnetic fields are present. If B = (400 µT) i, find the electric field E.
i. j. k2. F=ma
F=qv cross B
3. I tried finding F through one of the ways listed above, and tried using F=Eq equation to get E. However, i got different values for the force and cannot seem to get the answer.

 

[member 553083]

F = qv x B F = 11.0e-31 x (11.0, 16.0, 0) x (4 x 10-6, 0, 0) F = 4.88e-28 i + 0 j + 0 kE = F/q E = 4.88e-28/11.0e-31 E = 4.42 x 10^2 N/C or 442 N/C