Radius of path of electron in a magnetic field

In summary, the conversation discusses the calculation of the radius of the circular path that electrons follow in a uniform magnetic field. The value for the magnetic field is given as 50 Oersted, and the velocity of the electrons is 8.8 x 10^6 cm/sec. The formula for Lorentz force in C.G.S system is mentioned, and the final calculated value for the radius is 3.3 x 10^(-13) cm. However, the speaker realizes that there may be a mistake in the formula used and suggests a correction to get a more reasonable answer.
  • #1
Amith2006
427
2
# Electrons are moving in a uniform magnetic field of 50 Oersted having a velocity of 8.8 x 10^6 cm/sec. What is the radius of the circular path they follow?
I solved it in the following way:
In C.G.S system 1 Gauss = 1 Oersted (In vacuum)
So, B = 50 Gauss
V = 8.8 x 10^6 cm/sec
Let e be the charge of the electron, r be radius of its circular path and m be its mass.
e = 1.6 x 10^(-19) Coulomb = 4.8 x 10^(-10) Stat Coulomb
m = 9.1 x 10^(-28) grams
In a perpendicular magnetic field,
BeV = {m(V^2)}/r
r = (mV)/(Be)
Solving I get,
r = 3.3 x 10^(-13) cm
I think somewhere I have gone wrong as the radius is too small. Please help.
 
Physics news on Phys.org
  • #2
In cgs units the formula for the Lorentz force is (qv/c) x B. The final formula should read r = (mVc/Be). This gaves a much more reasonable answer.
 
  • #3
I have learned the expression for Lorentz force in C.G.S system.Thanks.
 

1. What is the equation for determining the radius of the path of an electron in a magnetic field?

The equation is given by r = mv/qB, where r is the radius, m is the mass of the electron, v is its velocity, q is its charge, and B is the strength of the magnetic field.

2. How does the strength of the magnetic field affect the radius of the electron's path?

The radius of the electron's path is directly proportional to the strength of the magnetic field. This means that as the magnetic field becomes stronger, the radius of the path will also increase.

3. Can the radius of the electron's path be altered by changing the speed or charge of the electron?

Yes, the radius of the electron's path can be altered by changing the speed or charge of the electron. As seen in the equation, the radius is directly proportional to the velocity and inversely proportional to the charge of the electron.

4. What is the direction of the electron's path in a magnetic field?

The direction of the electron's path is perpendicular to both the velocity of the electron and the direction of the magnetic field. This is known as the right-hand rule.

5. How does the radius of the electron's path change if the magnetic field is increased?

If the magnetic field is increased, the radius of the electron's path will also increase. This is because the strength of the magnetic field directly affects the force acting on the electron, causing it to move in a larger circular path.

Similar threads

  • Advanced Physics Homework Help
Replies
1
Views
980
  • Advanced Physics Homework Help
Replies
1
Views
957
  • Advanced Physics Homework Help
Replies
5
Views
2K
  • Introductory Physics Homework Help
Replies
6
Views
736
  • Advanced Physics Homework Help
Replies
1
Views
992
  • Advanced Physics Homework Help
Replies
4
Views
1K
  • Advanced Physics Homework Help
Replies
4
Views
3K
Replies
3
Views
2K
  • Advanced Physics Homework Help
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
1K
Back
Top