Today
we investigate the motion of a charge in a uniform electric field. The
electric field is 200 N/C and is in the positive *x*-direction. The
particle has charge 10m C, mass 10 g and is
at the origin, moving along the *y*-axis at 10m/s at time *t*=0.
When does the particle reach *x* = 1 m? What is its *y* coordinate
then?

The particle's acceleration is in the x-direction, with

This acceleration is constant, so the particle's motion in the x-direction
is described by equation 2.11 with *v*_{i} = 0.

Then