Wire coil in decreasing magnetic field

In summary, a wire coil with 10 turns and a radius of 2 cm is placed in a magnetic field of 2 T, which is perpendicular to the plane of each turn. The coil is wired in series with a resistor of 5 Ω. The magnetic field decreases at a constant rate to 0 T in 10 ms. To find the current through the resistor, Faraday's law of induction can be used, which states that the induced electromotive force (EMF) is equal to the rate of change of magnetic flux through a circuit. Using this law, the current can be calculated by dividing the induced EMF by the resistance of the circuit.
  • #1
Pete Panopoulos
3
0

Homework Statement


A wire coil of 2 cm with 10 turns is in a magnetic field of 2 T. The field is perpendicular to the plane of each turn of the coil. The coil is wired in series with resistor of 5 Ω. The field drops at a constant rate to 0.0 T in 10 ms. What is the current through the resistor?

Homework Equations


V=IR
Possibly F=ILxB ?
Magnetic Flux= B⋅dA = Bπr2

The Attempt at a Solution


I=V/R

We know that the magnetic field drops from 2T to 0T in .01 seconds, or -200T/s

and the Resistor is 5 Ω

Flux= B⋅dA = Bπ(.02)2

I'm assuming I'm missing a link to these things in my head any help would be appreciated
 
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  • #2
Can you bring in Faraday's law of induction?
 

1. What is a wire coil in a decreasing magnetic field?

A wire coil in a decreasing magnetic field refers to a setup where a coil of wire is placed in a magnetic field that is decreasing in strength over time. This can be achieved by either moving the coil away from the source of the magnetic field or by decreasing the strength of the magnetic field itself.

2. How does a wire coil in a decreasing magnetic field produce an electric current?

When a wire coil is placed in a changing magnetic field, it experiences a change in flux, which induces an electric current in the coil. This is known as electromagnetic induction, where the changing magnetic field creates a changing electric field, which in turn produces a current in the wire.

3. What factors affect the magnitude of the induced current in a wire coil?

The magnitude of the induced current in a wire coil depends on several factors, including the strength of the magnetic field, the rate of change of the magnetic field, the number of turns in the coil, and the resistance of the wire. A stronger magnetic field, a faster rate of change, more turns in the coil, and lower resistance will result in a larger induced current.

4. How is the direction of the induced current determined in a wire coil in a decreasing magnetic field?

The direction of the induced current in a wire coil is determined by the direction of the changing magnetic field. According to Lenz's Law, the induced current will flow in a direction that opposes the change in the magnetic field. This means that if the magnetic field is decreasing, the induced current will flow in a direction that creates a magnetic field that opposes the decrease.

5. What are some real-world applications of a wire coil in a decreasing magnetic field?

A wire coil in a decreasing magnetic field has many practical applications, such as in electric generators and transformers. It is also used in technologies like induction cooktops and wireless charging, where the changing magnetic field induces a current in a coil to power devices. Additionally, this concept is essential in understanding the behavior of electromagnetic waves, such as radio waves and light.

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