[Magnetism] Determine the direction of the force experienced by a (+)C

Click For Summary
The discussion revolves around determining the direction of the magnetic force on a positively charged particle (proton) in a magnetic field. The calculations for the force using the formula F = Bqvsinθ yield a force of 8.7*10^-14 N. However, there is confusion regarding the direction of the force, as the participant's application of the right-hand rule suggests the force is into the page, while the provided solution indicates it should be out of the page. The consensus is that the provided solutions may contain errors, and the participant's understanding of the right-hand rule is correct. The conversation highlights the importance of verifying solutions and understanding magnetic force direction.
Abood
Messages
14
Reaction score
3
Homework Statement
A proton travels with a speed of 3.0*10^6 m/s at an angle of 37 (degrees) west of north. A magnetic field of 0.30 T points to the north. Determine the following:
a) the magnitude of the magnetic force on the proton.
b) The direction of the magnetic force on the proton.
c) The proton's acceleration as it moves through the magnetic field
Relevant Equations
(Magnetic Force equations and Newton's Second Law)
F = Bvqsinθ
F = BILsinθ
F= ma

Alternative Right Hand Rule
Given:
q = 1.6*10^-19 C
B = 0.3 T north
v = 3*10^6 m/s north-west
θ = 37 (degrees)

Solution Attempt:
a) F = Bqvsinθ = (0.3)(1.6*10^-19)(3*10^6)(sin(37)) = 8.7*10^-14 N
b) Via right hand rule, F is into the page
c) a = F/m = 8.7*10^-14/1.6 × 10^−27 = 5.4*10^13 m/s^2

When I checked my answers with the given solutions, I found that answer b is incorrect which I didn't understand why.

I pointed the proton's direction to the west, the field to the north, and found my palm going inwards (into the page) but the solution shows that it should be out of the page. Did I do something incorrectly?
 
Physics news on Phys.org
Abood said:
Did I do something incorrectly?
Don't think so. Given solutions can be in error, too.
 
  • Like
Likes Abood
BvU said:
Don't think so. Given solutions can be in error, too.
I see, thank you very much!
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

Similar threads

  • · Replies 26 ·
Replies
26
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 10 ·
Replies
10
Views
8K
Replies
11
Views
3K
  • · Replies 15 ·
Replies
15
Views
2K
  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 1 ·
Replies
1
Views
3K