amacorrit80

2022-07-20

Does heating an electromagnet cause change in its magnetic field as well and vice versa?

Tolamaes04

Beginner2022-07-21Added 12 answers

your electromagnet is an inductor powered by a battery with constant potential $V$. The magnetic field is proportional to the intensity running on the wires. $B\propto I$. We know: $V=RI$, where $R$ is the resistance of the inductor. Its a very simple model as you can see...

For a small variation of temperature from initial temperature ${T}_{0}$, the resistance can be approximated with a linear relation:

$R=R({T}_{0})[1+\alpha (T-{T}_{0})]$

find $\alpha $ for a given material arround ${T}_{0}$ that you want to work with. So, in the vicinity of ${T}_{0}$, and with the temperature coeficient $\alpha $ measured/given, we can now conclude:

- If $\alpha >0$, resistance increases, current decreases, magnetic field decreases.

- If $\alpha <0$, resistance decreases, current increases, magnetic field increases.

- If $\alpha =0$, resistance decreases, current increases, magnetic field increases.

Temperature coeficient arround ${T}_{0}=293K$

For a small variation of temperature from initial temperature ${T}_{0}$, the resistance can be approximated with a linear relation:

$R=R({T}_{0})[1+\alpha (T-{T}_{0})]$

find $\alpha $ for a given material arround ${T}_{0}$ that you want to work with. So, in the vicinity of ${T}_{0}$, and with the temperature coeficient $\alpha $ measured/given, we can now conclude:

- If $\alpha >0$, resistance increases, current decreases, magnetic field decreases.

- If $\alpha <0$, resistance decreases, current increases, magnetic field increases.

- If $\alpha =0$, resistance decreases, current increases, magnetic field increases.

Temperature coeficient arround ${T}_{0}=293K$

The magnetic field inside a long straight solenoid carrying current

A)is zero

B)increases along its radius

C)increases as we move towards its ends

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Hertz

Watt

Newton

PascalWhat does tangential force produce?

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Which of the following correctly describes the magnetic field near a long straight wire?

A. The field consists of straight lines perpendicular to the wire

B. The field consists of straight lines parallel to the wire

C. The field consists of radial lines originating from the wire

D. The field consists of concentric circles centered on the wireIs energy directly proportional to frequency?

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Magnetic field lines never intersect each other because

There will be two directions of the field at the same point.

Feild lines repel each other

Field lines follow discrete paths only

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Towards 20 A

Towards 40 A

Zero

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A) 486 nm, Blue

B) 576 nm, Blue

C) 650, Blue

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Which of the following radiation has the shortest wavelength.

X-ray

Infra red

microwave

ultravioletHow to find the local extrema for $f\left(x\right)=5x-{x}^{2}$?