Ranking Forces on a Charged Particle in Uniform Electric and Magnetic Fields

AI Thread Summary
The discussion revolves around ranking the forces acting on a positively charged particle in various uniform electric and magnetic field scenarios (cases A-G). The participant correctly identifies that in case B, where the magnetic field is parallel to the velocity, there is no force acting on the particle. Cases A, C, D, and F all produce similar forces, while case E has a force of the same magnitude but in the opposite direction. Case G is considered the strongest due to the presence of two forces. The participant receives confirmation that their ranking and reasoning are accurate.
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Homework Statement



The below region of space shown has uniform electric and/or magnetic fields, dependent on the conditions listed for cases A-G. Identical positively charged particles enters these regions with the same velocity.

Rank the magnitude of the force on the particle just after it enters these regions for cases A-G from greatest to least.

Untitled.png


Homework Equations



F = qE + qv x B
F = qE
Fb = qvBsin(*)

The Attempt at a Solution



A) Since the particle is positive(+) I said there would be a force F namely ( ---> ) on the particle.

B) When only B is present there is no force on the particle, Fb = qvBsin(0) = 0. This is because both B and V are parallel.

C) Same as A: ( ---> )

D) Same as A: ( ---> )

E) Here the direction of the force changes but its magnitude remains the same so: ( <--- )

F) There is an upwards force in this case. However, its magnitude is the same as was in A.

G) I have this as being two forces on the particle so G is the largest.

Overall I ranked them as follows: G>A=C=D=E=F>B

Not sure if I did these correctly any help would be appreciated.


 
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vysero said:

Homework Statement



The below region of space shown has uniform electric and/or magnetic fields, dependent on the conditions listed for cases A-G. Identical positively charged particles enters these regions with the same velocity.

Rank the magnitude of the force on the particle just after it enters these regions for cases A-G from greatest to least.

View attachment 80877

Homework Equations



F = qE + qv x B
F = qE
Fb = qvBsin(*)

The Attempt at a Solution



A) Since the particle is positive(+) I said there would be a force F namely ( ---> ) on the particle.

B) When only B is present there is no force on the particle, Fb = qvBsin(0) = 0. This is because both B and V are parallel.

C) Same as A: ( ---> )

D) Same as A: ( ---> )

E) Here the direction of the force changes but its magnitude remains the same so: ( <--- )

F) There is an upwards force in this case. However, its magnitude is the same as was in A.

G) I have this as being two forces on the particle so G is the largest.

Overall I ranked them as follows: G>A=C=D=E=F>B

Not sure if I did these correctly any help would be appreciated.


Sounds ok to me.
 
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Dick said:
Sounds ok to me.

Wait... you mean I got it right.. like on my own ._. I think I will go have a drink!
 
vysero said:
Wait... you mean I got it right.. like on my own ._. I think I will go have a drink!

Sure, have a drink. I can't see anything wrong with your logic.
 
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