An electron is initially moving to the right at 2.50 x 106 m/s. It enters a region of space where there is a constant electric field of magnitude 0.125 mN/C and directed upward. (a) In which direction will the electron accelerate? Explain. (b) What will be the shape of the electron's trajectory? (c) During a certain amount of time in the electric field, the electron moves 25.0 cm to the right. How far does it move vertically during this time?
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a) the electron will accelerate downward.
( the electron has the negative charge, the electron will experience the force on opposite direction with the electric field)
b) the shape of the electron's trajectory is parabolic
c) x = v * t
--> t = x/v = 0.25/2.5 x 10^6 = 1 x 10^-7 sec
y = (1/2) a * t^2 ---> a = q*E/m
= (1/2) * (q*E/m) * t^2
= (1/2) * (1.6 x 10^-19 * 0.125 x 10^-3/9.11 x 10^-31) * (1 x 10^-7)^2
= 1.10 x 10^-7 m
( the electron has the negative charge, the electron will experience the force on opposite direction with the electric field)
b) the shape of the electron's trajectory is parabolic
c) x = v * t
--> t = x/v = 0.25/2.5 x 10^6 = 1 x 10^-7 sec
y = (1/2) a * t^2 ---> a = q*E/m
= (1/2) * (q*E/m) * t^2
= (1/2) * (1.6 x 10^-19 * 0.125 x 10^-3/9.11 x 10^-31) * (1 x 10^-7)^2
= 1.10 x 10^-7 m