Torques between revolving magnet bars

In summary, revolving magnet bars create an interaction between magnetic fields, resulting in a torque force that causes them to rotate. This phenomenon is utilized in devices such as electric motors and generators, where the rotation of the magnet bars generates electricity. The strength of the torque depends on factors such as the strength of the magnetic fields, the distance between the bars, and the speed of rotation. Understanding torques between revolving magnet bars is crucial in designing and optimizing these devices for various applications.
  • #1
Jackson Lee
77
1
Hey, guys, I find a interesting phenomenon. When an external magnetic field is applied on a current loop, the net torque will try to align the loop's dipole moment with the magnetic field.
And considering that electrical loops could be regarded as electromagnet, we change the current loop into a real magnet.However, at this time, the net external applied magnetic field try to align the magnet in the same line but the opposite direction with the applied field for opposite poles attract each other.
Why do this happen? Is there any problem to exchange current loop with a real magnet??
 
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  • #2
The N-S coupling results in the magnetic fields of the two magnets being in the same direction - not opposite directions. Think of two coil magnets being placed together length wise. If the South pole of one is touching the N pole of the other you have a double the length coil magnet with the N at one and and S at the other. The magnetic dipole moments of each coil are all aligned.

AM
 
  • #3
Andrew Mason said:
The N-S coupling results in the magnetic fields of the two magnets being in the same direction - not opposite directions. Think of two coil magnets being placed together length wise. If the South pole of one is touching the N pole of the other you have a double the length coil magnet with the N at one and and S at the other. The magnetic dipole moments of each coil are all aligned.

AM
Thanks, I have got it.
 
  • #4
Good question, though. I had to think about it.

AM
 
  • #5
Andrew Mason said:
Good question, though. I had to think about it.

AM
Besides, I want to ask a another question. The emf of a coil is the rate of change of flux or flux linkage? Because I was totally confused by internal inductance of a long straight line, why we need only consider a fraction of total current.
 
  • #6
Andrew Mason said:
Good question, though. I had to think about it.

AM
If you are free and interested in this topic, you can view this---https://[URL="https://www.physicsforums.com/threads/confusion-about-inner-inductance-of-transmission-line.802716/"]www.physicsforums.com/threads/confusion-about-inner-inductance-of-transmission-line.802716/[/URL]
Thanks very much
 
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Related to Torques between revolving magnet bars

1. What is the purpose of studying torques between revolving magnet bars?

The purpose of studying torques between revolving magnet bars is to understand the forces and interactions involved when two magnets are in motion. This can have practical applications in various fields, such as engineering, physics, and material science.

2. How are torques between revolving magnet bars calculated?

Torques between revolving magnet bars are calculated using the equation T = m x B, where T is the torque, m is the magnetic moment, and B is the magnetic field strength. Other factors such as the distance between the magnets and their orientation also play a role in the calculation.

3. Can torques between revolving magnet bars be controlled?

Yes, torques between revolving magnet bars can be controlled by adjusting the parameters that affect the calculation, such as the magnetic field strength or the distance between the magnets. Additionally, the use of other materials or structures can also influence the torque between the magnets.

4. What factors can affect the torque between revolving magnet bars?

The torque between revolving magnet bars can be affected by various factors, such as the strength of the magnets, the distance between them, the orientation of the magnets, and the presence of other materials or structures in the surrounding environment.

5. What are the potential applications of torques between revolving magnet bars?

The study of torques between revolving magnet bars has potential applications in fields such as motors and generators, magnetic levitation systems, and magnetic data storage devices. Understanding and controlling these torques can also lead to advancements in renewable energy and transportation technologies.

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