posted by Taylor on .
An electron that has a horizontal initial speed of 4.50 106 m/s enters a region that has an electric field of 120 V/m pointing vertically upward.
(a)How long does the electron take to travel 9 cm in the horizontal direction?
(b) In this same time, what is the vertical displacement of the electron? Treat up as positive.
(a) Divide 0.09 meters by the horizontal speed component, which remains constant.
t = 0.09 m/4.5*10^6 m/s = ____ s
(b) First compute the acceleration in the vertical direction,
a = e*E/m
e and m are the electron charge and mass. Look them up.
The electron will accelerate down due to its negative charge in a positive E field.
The distance travelled in time t is
Y = (1/2) a t^2