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

In summary, the magnetic field has a magnitude of 4.5x10^-5 T at time t and points in the positive z-direction. A rectangular wire loop with dimensions 0.3m by 0.4m lies in the xy-plane. The induced emf in the loop is 0.312x10^-7V and the current is 3.18x10^-7A when the resistance is 10 ohms. To re-orient the loop so that the induced emf is only 40% of the value found in part (a), the normal to the plane of the loop should be at an angle of 66.4 degrees w.r.t. the z-axis.
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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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  • #2
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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1. What is induced electromotive force (EMF)?

Induced EMF is the voltage or electric potential difference that is created in a conductor when it is exposed to a changing magnetic field. This phenomenon is described by Faraday's law of induction and plays a crucial role in electromagnetic induction.

2. How do you calculate induced EMF?

The induced EMF can be calculated using the equation: EMF = -N(dΦ/dt), where N is the number of turns in the coil and dΦ/dt is the rate of change of the magnetic flux through the coil. This equation is derived from Faraday's law of induction.

3. Can you explain the process of checking equations for accuracy?

To check equations for accuracy, you should first ensure that all the variables and their units are correctly identified and used in the equation. Then, you can plug in known values and solve the equation to see if it matches the expected result. Additionally, you can also use mathematical software or tools to verify the equation and its solutions.

4. What are some common mistakes when working on an induced EMF problem?

One common mistake is forgetting to take into account the negative sign in the induced EMF equation. Another mistake is using incorrect units for the variables, which can lead to incorrect solutions. It is also important to carefully consider the direction of the magnetic field and the direction of movement of the conductor when solving induced EMF problems.

5. How can I improve my understanding of induced EMF problems?

To improve your understanding of induced EMF problems, it is important to have a solid understanding of the underlying concepts of electromagnetism and electromagnetic induction. You can also practice solving different types of problems and seek help from resources such as textbooks, online tutorials, and peer-reviewed articles. Additionally, seeking guidance from a mentor or teacher can also be beneficial.

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