Need someone to check my equations and work on this induced EMF problem

AI Thread Summary
The discussion centers on calculating the induced electromotive force (emf) in a rectangular wire loop placed in a changing magnetic field. The induced emf was calculated as 0.312x10^-7 V, and the current through the loop, given its resistance of 10 ohms, was found to be 3.18x10^-7 A. There were suggestions to double-check the arithmetic and scientific notation in these calculations. The direction of the current was also discussed, emphasizing that it should oppose the change in the magnetic field, and it was noted that the loop's normal should be oriented at 66.4 degrees to the z-axis for a desired emf reduction. Accurate calculations and clear diagrams are essential for understanding the problem fully.
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Homework Statement
a magnetic field has a magnitude at time t of 4.5x10^-5 T +(2.6x10^-6 T/sec)t. the field points in the positive z-direction.
a rectangular wire loop, which is 0.3 meters by 0.4 meters, lies in the xy-plane.
Note: If the z axis points out of the paper.

a.) What is the induced emf in the loop?

b.) If the wire loop has a resistance of 10 ohms, what is the current in the loop? In a clear diagram, indicate the direction in which that current travels.

c.) How could you re-orient the loop so that the induced emf was only 40% of the value of the value had to find in part (a)?
Relevant Equations
a.) Vinduced= dB/dt*A
b.) I=Vinduced/R
c.) 0.4Vinduced=Vinducedcos(theta)
a magnetic field has a magnitude at time t of 4.5x10^-5 T +(2.6x10^-6 T/sec)t. the field points in the positive z-direction.
a rectangular wire loop, which is 0.3 meters by 0.4 meters, lies in the xy-plane.
Note: If the z axis points out of the paper.

a.) What is the induced emf in the loop?
(2.6x10^-6)(0.12m^2)=0.312x10^-7V

b.) If the wire loop has a resistance of 10 ohms, what is the current in the loop? In a clear diagram, indicate the direction in which that current travels.
I=(0.312x10^-7V)/(10ohm)= 3.18x10^-7V

c.) How could you re-orient the loop so that the induced emf was only 40% of the value of the value had to find in part (a)?
0.4=cos(theta)
theta=66.42degrees
90-23.58degrees
 
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Maybe my arithmetic is wrong, but I think you have a couple of careless errors in the exponents and scientific notation of parts (a) and (b). Please double-check your answers there. ## \\ ## Also you need to determine the direction of the current for part (b). To describe it without a diagram, looking at the loop with positive z-pointing at you, is the current clockwise or counterclockwise? For a hint at this part, the magnetic field created from any current flow must oppose the change in the magnetic field that is occurring. ## \\ ## For part (c), you got it pretty much correct, but the normal to the plane of the loop needs to be at angle 66.4 degrees w.r.t. the z-axis. That is how such an orientation is normally described.
 
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