What is the force on a wire in a magnetic field?

AI Thread Summary
The discussion focuses on calculating the force on a wire in a magnetic field. For a wire carrying a 9.80-A current perpendicular to a 0.80-T magnetic field, the force per meter is expressed as F = 7.84 x L, where L is the length of the wire. The challenge arises from not knowing the length L, which is essential for determining the total force. When the angle between the wire and the magnetic field is 45°, the force can be calculated using F = ILB sin θ. The conversation emphasizes the importance of understanding the relationship between current, magnetic field strength, and the angle to find the force.
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Question: 1. a) what is the force per meter on a wire carrying a 9.80-A current when perpendicular to a 0.80-T magnetic field? b) What if the angle between the wire and the field is 45°?

For part a) I know that F = ILB, where I is the current, L is the length of the wire and B is the size of the magnetic field.

Therefore F = 9.80 x L x 0.80
= 7.84 x L

But how can you work out the force when you don’t know what L is?

For part b) I know that F = ILB sin θ

I’m not sure how to approach the problem other than what I have expressed. Any help you can offer will be great...thanks :D
 
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-_-' said:
Question: 1. a) what is the force per meter on a wire carrying a 9.80-A current when perpendicular to a 0.80-T magnetic field? b) What if the angle between the wire and the field is 45°?

For part a) I know that F = ILB, where I is the current, L is the length of the wire and B is the size of the magnetic field.

Therefore F = 9.80 x L x 0.80
= 7.84 x L

But how can you work out the force when you don’t know what L is?
The clue is in the question :wink:
 
oh yeh! Thanks so much! :D
 
-_-' said:
oh yeh! Thanks so much! :D
My pleasure :smile:
 
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