I got the formula, what does the angle effect? Net Magnetic force

AI Thread Summary
The discussion revolves around calculating the net magnetic force on a bent wire in a uniform magnetic field, with specific attention to the angle of 62° between the wire and the x-axis. The user is seeking clarification on how to apply the cross product in the context of magnetic force calculations, specifically how the angle affects the force. They reference the formula for total magnetic force, noting that the angle plays a crucial role in the cross product, which involves the sine of the angle. There is confusion regarding whether the forces acting on the wire would cancel each other out, resulting in a net force of zero. Understanding the application of the cross product and the impact of the angle is essential for solving the problem accurately.
mr_coffee
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Hello everyone, I think I am missing this problem because there is an angle invovled, but it doesn't seem to matter what angle it is from what my lecture notes say. but here's the question:
The bent wire shown in Fig. 28-39 lies in a uniform magnetic field. Each straight section is 2.1 long and makes an angle of = 62° with the x axis, and the wire carries a current of 2.0 A. What is the net magnetic force on the wire in unit-vector notation if the magnetic field is given by each of the following?
Here is the picture:
http://www.webassign.net/hrw/28-39.gif

Here is my work:
http://show.imagehosting.us/show/891660/0/nouser_891/T0_-1_891660.jpg
any ehelp would be great! :smile:

THe formula states: Fbtotal= F1 + F2 + F3 + ... + Fn then it says: F = I(L1 + L2 +...+Ln) x B
 
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Right, the angle comes in with the cross product at the end..
 
can you expland that explanation alittle more? How do you apply the cross product with the angle? I know the dot product has like AB = cos/|A||B| but i never heard of one for the cross product of A B.
 
The magnitude of \vec A \times \vec B is AB \sin {\theta}.
 
Wouldn't both the forces be equal and just opposite in direction therefor the net force is zero??
 
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