Calculating distance of an electron moving between 2 plates

In summary, an electron is accelerated from rest by a potential difference of 1.0 x 10^3 volts and passes midway between two flat parallel plates. The electric field between the plates has a magnitude of 2.0 x 10^3 N/C. The electron is deflected (x) from it's original horizontal path by the time that it reaches the other end of the plates. First, find the acceleration, then find the distance between starting position and the end of the plates, and finally find the distance between starting position and the start of the plates. Finally, find the final velocity.
  • #1
Combine
15
0

Homework Statement


Electrons are accelerated from REST by a potential difference of 1.0 x 10^3 volts
They pass midway between two flat parallel plates 0.15m long and 0.030m apart. The electric field between the plates has a magnitude of 2.0 x 10^3 N/C. Determine how far an electron will be deflected (x) from it's original horizontal path by the time that it reaches the other end of the plates

I can't use most of the formulas because there is constant acceleration involved after it reaches the 0.35 m mark, thus I can't get a x nor a y and the acceleration is just in the X axis,
I'm really stuck!

can anybody please help me?

Homework Equations


e = 1.602 x 10^-19
m = 9.11 x 10^-11
k = 9.0 x 10^9 N M^2/C^2

ε = V/r
ε = Fe/q
Vf^2 = Vi^2 + 2ad
d = v2t - 1/2at^2
d = v1t - 1/2at^2

The Attempt at a Solution


First find the acceleration
F = ma
qε = ma
(1.602x10^-19)(2000) = 9.11 x 10^-31a
a = 3.52 x 10^14

next find the distance between starting position and the end of the plates
ε = V/r
2000 = 1000/r
r = 0.50

after that find the distance between starting position and the start of the plates
0.50 - 0.15 = 0.35m

next you find the final velocity (the second before the electron reach's the plates)
Vf^2 = Vi^2 + 2(3.52x10^24)(0.35)
vf = 1.6 x 10^7
 

Attachments

  • Untitled.jpg
    Untitled.jpg
    6.2 KB · Views: 432
Last edited:
Physics news on Phys.org
  • #2
The first thing to do is calculate the velocity of electrons accelerated through 1000V
use eV = 0.5mv^2
These electrons then travel into the space betwen the parallel plates where they experience a vertical force.
Hope this helps
 
  • #3
Well it only kinda helped, I am still unsure if that is the answer.

eV = 1/2mv^2
1.602 x 10^-16 = 4.555 x x10^-31V^2

v = 1.9 x 10^7

t = 0.15/1.9 x 10^7
t = 7.0 x 10^-9

d = V1t + 1/2at^2
d = 0 + 1/2(3.52 x 10^14)(7.0 x 10^-9)
d = 0.008624

The answer makes logical sense, because we know that the space between the plates is 0.030m

and it's only deflected a bit so it would make sense that the vertical deflection would be 0.008624m

can anyone confirm this?
 

Related to Calculating distance of an electron moving between 2 plates

What is the formula for calculating the distance of an electron moving between 2 plates?

The formula for calculating the distance of an electron moving between 2 plates is:

d = (V/magnetic field strength) x (time it takes for electron to cross the plates)

What units should be used when calculating the distance of an electron?

The units used for calculating the distance of an electron are meters (m) for distance, volts (V) for potential difference, tesla (T) for magnetic field strength, and seconds (s) for time.

How does the speed of the electron affect the distance it travels between the plates?

The speed of the electron does not directly affect the distance it travels between the plates. The distance is determined by the applied potential difference and the time it takes for the electron to cross the plates.

Can the distance of an electron be calculated if the magnetic field strength is unknown?

No, the distance of an electron cannot be accurately calculated if the magnetic field strength is unknown. The magnetic field strength is a crucial factor in the calculation formula and must be known in order to obtain an accurate result.

Are there any other factors that may affect the accuracy of the calculated distance of an electron?

Yes, there are other factors that may affect the accuracy of the calculated distance of an electron. These include the presence of external magnetic fields, the shape and orientation of the plates, and the presence of other charged particles in the environment.

Similar threads

  • Introductory Physics Homework Help
Replies
6
Views
2K
  • Introductory Physics Homework Help
Replies
3
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
1K
  • Introductory Physics Homework Help
Replies
28
Views
3K
  • Introductory Physics Homework Help
Replies
3
Views
6K
  • Introductory Physics Homework Help
Replies
5
Views
1K
  • Introductory Physics Homework Help
Replies
2
Views
1K
  • Introductory Physics Homework Help
Replies
9
Views
7K
  • Introductory Physics Homework Help
Replies
4
Views
922
  • Introductory Physics Homework Help
Replies
13
Views
1K
Back
Top