Magnitude and Direction of induced voltage

In summary, the conversation is about a physics e&m question involving finding the magnitude of the induced voltage using Faraday's Law and Lenz's Law. There is a discussion about whether to include a constant "c" and determining the direction of the current flow using the right hand rule. The conversation also includes a calculation of flux and determining the area of the shape in question. There is a brief discussion about accounting for different flux values and the direction of the current.
  • #1
rzn972
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0

Homework Statement


Hey everyone I have a physics e&m question: [/B]
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Homework Equations

The Attempt at a Solution



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I took the derivative to find the magnitude of the induced voltage. (do I need to add a constant c?)
I am having trouble with the direction of the current flow though... Do I use the right hand rule?

Thanks![/B]
 

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  • #2
rzn972 said:
I took the derivative to find the magnitude of the induced voltage. (do I need to add a constant c?)
I am having trouble with the direction of the current flow though... Do I use the right hand rule?
The constant "c" is usually either the speed of light in a vacuum or the constant of integration ... do either of these situation apply here?
The current flow is determined by the right hand rule in conjunction with a law of physics that applies to induced currents.
I'm puzzled you started at (c) ... did you do (a) and (b)?
 
  • #3
4 a) Does the question ask for the magnetic (flux) ?

Oh, it should read the magnitude, not magnetic!

Shouldn't you use Faraday's law?
 
  • #5
There might be a small gap in the lower right-hand part of the loop
 
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  • #6
Well spotted - there may well be.
 
  • #7
Sorry! Yeah I meant magnitude.
 
Last edited:
  • #8
Okay so the derivative of magnetic flux is the induced voltage. I am having trouble calculating flux. Flux = BA cos (theta). How do I get the area...?
 
  • #9
What shape is the area in question?
 
  • #10
Ahh I forgot that they gave us the length of the square. I think I was able to get it.
13149837_10208152309959848_930633277_n_zpsdro9gsiq.jpg

Does this look right?
 
  • #11
in (c) and (d) the flux density is different in different parts of the square, how did you account for this?
(hint: the variable y should not be in your answer)
in (b) the question asks for the direction of the current
 
  • #12
For b) I say it is counterclockwise. My reasoning is that the field is decreasing as time passes (e^(-t)). The field will want to come out and the way to do that is for the induced current to flow counterclockwise.

I am not clear on c). Doesn't the y variable account for the different flux values for different y values?
 

Related to Magnitude and Direction of induced voltage

1. What is the relationship between the magnitude of induced voltage and the strength of the magnetic field?

The magnitude of induced voltage is directly proportional to the strength of the magnetic field. This means that as the magnetic field increases, the induced voltage also increases.

2. How is the direction of induced voltage determined?

The direction of induced voltage is determined by the direction of the change in the magnetic field. If the magnetic field is increasing, the induced voltage will have a certain direction, and if the magnetic field is decreasing, the induced voltage will have the opposite direction.

3. What factors can affect the magnitude of induced voltage?

The magnitude of induced voltage can be affected by the rate at which the magnetic field changes, the number of turns in the coil, and the strength of the magnetic field. It can also be affected by the material of the coil and the resistance of the circuit.

4. Can induced voltage be negative?

Yes, induced voltage can be negative. This can occur when the change in the magnetic field is in the opposite direction of the current flow. In this case, the induced voltage will oppose the current flow and result in a negative value.

5. How is the magnitude of induced voltage calculated?

The magnitude of induced voltage can be calculated using Faraday's Law, which states that the magnitude of induced voltage is equal to the rate of change of magnetic flux through a coil. It can be represented by the equation V = -N(dΦ/dt), where N is the number of turns in the coil and dΦ/dt is the rate of change of magnetic flux.

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