Magnetic Fields and total force

[Baracabacca]

Help!

Given that B = (6x, -9y, 3z) find the total force experienced by a rectangular loop in the z = 0 plane:

Loop defined as...
1<x<3
1<y<2

with 5 Amp current flowing COUNTERclockwise.

 

[marlon]

Help!

Given that B = (6x, -9y, 3z) find the total force experienced by a rectangular loop in the z = 0 plane:

Loop defined as...
1<x<3
1<y<2

with 5 Amp current flowing COUNTERclockwise.

1) according to our guidelines, you need to show us what you have done
2) what is the formula that you would use here ?
3) are you sure you have all the data that you need ?

marlon

 

[Baracabacca]

1) I guess I got a little anxious with the submit button!

I'm having problems setting up the equation.

2) I believe we're to use the equation: F = Int(dl x B) (where "x" indicated a cross product.)

I know I need to apply superposition to the loop - doing the integral for each of the four sides of the loop.

My problem comes from finding dl. Maybe I'm approaching the problem from the wrong angle. I initially thought you would use the integral relating B and the length of the loop in differential form.

3) I've submitted all information given, but I'm unclear if there's an intermediate step to solve extra needed data.

 

[OlderDan]

1) I guess I got a little anxious with the submit button!

I'm having problems setting up the equation.

2) I believe we're to use the equation: F = Int(dl x B) (where "x" indicated a cross product.)

I know I need to apply superposition to the loop - doing the integral for each of the four sides of the loop.

My problem comes from finding dl. Maybe I'm approaching the problem from the wrong angle. I initially thought you would use the integral relating B and the length of the loop in differential form.

3) I've submitted all information given, but I'm unclear if there's an intermediate step to solve extra needed data.

Sinde the field is constant, your integral reduces to a sum of four terms for the four sides of the loop, where each term is of the form (Bold is vector)

F = I L x B

 

[Baracabacca]

With that analysis I keep getting the total resultant force as zero. Does this make any sense?

 

[OlderDan]

With that analysis I keep getting the total resultant force as zero. Does this make any sense?

What happens to the force when you reverse the current in a wire? You have pairs of opposite currents, so it absolutely does make sense. Torque would be a different matter.

 

[Baracabacca]

That's right! Thank you so much for the help!