Magnetic Force on a Circuit: What is the Magnitude of Force on a Structure?

AI Thread Summary
The discussion centers on calculating the magnetic force on a structure using the formula |I(AC×B)|, where specific values for current, vector magnitudes, and angle are provided. The initial calculation yielded a force of 8 N, which was found to be incorrect according to the answer key. Participants confirm that options B, C, and D are correct, while there is some uncertainty regarding option A, which may be off by a factor of 21/2. Ultimately, the consensus is that all options in the answer key are indeed correct. The thread highlights the importance of verifying calculations in physics problems.
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Homework Statement


attachment.php?attachmentid=69003&stc=1&d=1398335923.png


(Ans: A,B,C,D)

Homework Equations


The Attempt at a Solution


The magnitude of force on the structure is given by

$$|I(\vec{AC}\times \vec{B})|=I|\vec{AC}||\vec{B}|\sin(\pi/4)$$
From the question, ##I=2\,A##, ##|\vec{AC}|=2\sqrt{2}\,m## and ##|\vec{B}|=2\,T##. Hence,
$$|F|=2\times 2\sqrt{2}\times 2 \times \frac{1}{\sqrt{2}}=8\,N$$
However, this is incorrect as per the answer key.

Any help is appreciated. Thanks!
 

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What does the answer key say?
 
dauto said:
What does the answer key say?

I already stated the answers below the image. The correct choices are A,B,C,D.
 
The key says they are all correct? I agree with you. A seems to be off by a factor 21/2
 
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dauto said:
The key says they are all correct? I agree with you. A seems to be off by a factor 21/2

Yes, all the options are correct. I already proved that B,C,D are correct, I was unsure about only the A option. Thanks dauto for the check! :)
 
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