Calculate Earth's Magnetic Flux at a Certain Location

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The Earth's magnetic field at a specific location has a magnitude of 5.6x10-5 T, directed 72 degrees below the horizontal. To calculate the magnetic flux through the top of a desk measuring 110 cm by 57 cm, the formula used is Φ = BA cos θ. An initial calculation yielded an incorrect result of 1.1e-5 Wb. The error was identified as using cosine instead of sine, as the desk's surface is horizontal and the magnetic field is not perpendicular to it. Correcting this mistake is essential for accurately determining the magnetic flux.
muffintop
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1. At a certain location, the Earth's magnetic field has a magnitude of 5.6x10-5 T and points in a direction that is 72 degrees below the horizontal. FInd the magnitude of the magnetic flux through the top of a desk at this location that measures 110 cm by 57 cm.
2. I used the formula \Phi = BA cos \theta

The Attempt at a Solution


\Phi[/thex] = 5.6x10<sup>-5</sup> x 1.10m x .57m x cos 72<br /> =1.1e-5 Wb and it&#039;s wrong
 
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muffintop said:
1. At a certain location, the Earth's magnetic field has a magnitude of 5.6x10-5 T and points in a direction that is 72 degrees below the horizontal. FInd the magnitude of the magnetic flux through the top of a desk at this location that measures 110 cm by 57 cm.

2. I used the formula \Phi = BA cos \theta

The Attempt at a Solution


\Phi[/thex] = 5.6x10<sup>-5</sup> x 1.10m x .57m x cos 72<br /> =1.1e-5 Wb and it&#039;s wrong
<br /> <br /> Welcome to PF.<br /> <br /> Is the desk top a vertical surface or a horizontal one?<br /> <br /> <a href="http://hyperphysics.phy-astr.gsu.edu/Hbase/magnetic/fluxmg.html" target="_blank" class="link link--external" rel="nofollow ugc noopener">http://hyperphysics.phy-astr.gsu.edu/Hbase/magnetic/fluxmg.html</a>
 
LowlyPion said:
Welcome to PF.

Is the desk top a vertical surface or a horizontal one?

http://hyperphysics.phy-astr.gsu.edu/Hbase/magnetic/fluxmg.html


Horizontal. and since the I'm looking for the magnetic flux, it should be perpendicular to the area so I use sine instead of cosine. What a stupid mistake haha, thank you for your help!
 
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