Question:
An electron in an oscilloscope tub is traveling horizontally with a speed of 3.9 x 106 m/s. It passes through a 2.0 c=m long region with an electric field pointing upward with a magnitude of 1500 N/C. What is the electron's velocity when it emerges from the electric field region?
The answer is 4.13 x 106, 91 degrees below the horizontal.
I just don't know how to solve it