An electron in a computer monitor enters midway between two parallel oppositely
ID: 2012179 • Letter: A
Question
An electron in a computer monitor enters midway between two parallel oppositely charged plates, as shown in the figure . The initial speed of the electron is 6.20×10^7 m/s and its vertical deflection (d) is 4.70 mm.What is the magnitude of the electric field between the plates and determine the magnitude of the surface charge density on the plates in C/m^2 .
Please include all steps in solving problem Thanks so much in advance!
Explanation / Answer
the length L = 10 cm = 0.1 mwidth W = 1 cm =0.01 m
separation of the plates d = 4.7 mm = 4.7 * 10 ^-3 m
Area of the plate A = LW = 10^-3 m^ 2
Initial speed of the electron u = 6.20 * 10 ^ 7 m / s
vertical deflection y = 4.7 * 10 ^-3 m
In horizontal direction :
distance S = L = 0.1 m
velocity u = 6.20 * 10 ^ 7 m / s
So, time t = S / u = 1.612 * 10 ^-9 s
In vertical direction :
distance y = 4.7 * 10 ^-3 m
Initial velocity U = 0
time t = 1.612 * 10 ^-9 s
from the relation y = Ut + ( 1/ 2) at^ 2
y = ( 1/ 2) at^ 2
from this accleration a = 2y / t^ 2
= 3.613 * 10 ^15 m / s^ 2
From Newton,s 2nn law, the force F= ma = Eq
from this electric field E = ma / q
here q = 1.6 * 10^-19 C (charge of electron )
m = 9.11 * 10 ^-31 kg ( mass of electron )
plug the values we get E = 20525 N / C (b) the surface charge density = 2(0)E here 0 = 8.85*10^-12 c^2/N-m = 363.29*10^-9 C/m^2 (b) the surface charge density = 2(0)E here 0 = 8.85*10^-12 c^2/N-m = 363.29*10^-9 C/m^2
Related Questions
Hire Me For All Your Tutoring Needs
Integrity-first tutoring: clear explanations, guidance, and feedback.
Drop an Email at
drjack9650@gmail.com
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.