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

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SUMMARY

The discussion focuses on calculating the induced electromotive force (emf) in a rectangular wire loop subjected to a time-varying magnetic field. The magnetic field is defined as 4.5x10^-5 T + (2.6x10^-6 T/sec)t, and the loop dimensions are 0.3 meters by 0.4 meters. The induced emf is calculated as 0.312x10^-7 V, leading to a current of 3.18x10^-7 A through a 10-ohm resistance. Additionally, to achieve an induced emf of 40% of the original value, the loop must be oriented at an angle of 66.42 degrees with respect to the z-axis.

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  • Knowledge of magnetic field strength and its time dependence
  • Familiarity with Ohm's Law and electrical resistance
  • Ability to calculate angles in trigonometry for loop orientation
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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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