Speed of electron in external magnetic field (1 Viewer)

[conman]

My question is just simple:
When an electron moves with particular speed into an external magnetic field. Is there a change in speed of an electron (before entering and after)?

 

[shinji]

umm not that i know of.

all that changes is the direction that the electron travels due to electrons charge and the magnetic field.

 

[conman]

umm not that i know of.

all that changes is the direction that the electron travels due to electrons charge and the magnetic field.

But according to text book, when a charged particle moves into an external magnetic field will experience a force which causes it to change the direction
F=qvBsin theta.
So you said that there are no change except for the direction. Which one is correct (only change in direction or both direction&speed)

 

[shinji]

from my understandin, the speed doesn't change.

the magnitude of the force is determined by the charge, velocity of the particle and the external magnetic field.

force only accounts for a change in direction of the particle.

But don't take my word for that, that's my understanding. You should get a second opinion~

 

[conman]

from my understandin, the speed doesn't change.

the magnitude of the force is determined by the charge, velocity of the particle and the external magnetic field.

force only accounts for a change in direction of the particle.

But don't take my word for that, that's my understanding. You should get a second opinion~

I think you are right. Force is determined by the charged and the velocity of the particle and magnitude of external magnetic field. It only changes the direction of the particle.

 

[helper]

Yep, the speed it constant but the direction changes, so the velocity changes and it is accelerating.

 

[twilight1412]

My question is just simple:
When an electron moves with particular speed into an external magnetic field. Is there a change in speed of an electron (before entering and after)?

the answer to your question is that the velocity changes
velocity
1.change in speed(m/s)
2.change in direction
the speed remains constant but the electron is deflected and therefore the direction changes meaning the velocity changes