Total Force on Wire: Solving a Physics Problem

AI Thread Summary
A physics problem involves a 50 cm wire bent at a right angle, with one section along the z-axis and the other along the line y=2x in the xy-plane, carrying a 20A current. The magnetic field is uniform at B=0.318i. The force on the z-axis section is calculated using F=BILsin(theta), yielding a force of 1.59 N. For the xy-plane section, the force is calculated as approximately 1.41 N. The user struggles to combine these forces correctly to find the total magnitude, indicating a potential misunderstanding in vector addition.
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Homework Statement


A stiff wire 50cm long is bent at a right angle in the middle. One section lies along the z axis and the other is along the line y=2x in the xy plane. A current of 20A flows in the wire down the z axis and out the line in the xy plane. The wire passes through a uniform magnetic field give by B=.318i. Determine the magnitude and direction of the total force on the wire.

Homework Equations


F=BILsin(theta)

The Attempt at a Solution


For the z axis part of the wire, I get F=(20)(.25)(.318)
For the xy plane part of the wire I get (20)(.25)(.318)(.447)
Now when i square these forces take the sum and square root the answer, I don't get the magnitude I should. This problem is pretty straight forward, not quite sure why I can't get it.

Thanks guys
 
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0.447 ≈ cos(θ), where θ is the angle the xy-plane portion of the wire makes with the x-axis (also the direction of the B field.

sin(θ) = 2/√(5) .
 
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