Electromagnetic force question

In summary, there is no energy generated by the relative weight of two magnets repelling each other. It is not possible to convert gravity into electricity. Any movement between the magnets would only result in temporary energy transfer, and as soon as the movement stops, there is no more energy output. This is similar to how a microphone works, but with the key difference being that power output depends on the change in field, not the field strength.
  • #1
Peter McKenna
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0
If two magnets, equally but oppositely charged, were placed one on top of the other, such that they repel each other, but the weight and shape would not allow the top magnet to slide off, what energy is generated by the relative weight (gravity acting on the mass) of the top plate overcoming the magnetic rejection force.

I realize there should be some heat. Provided the plates remained motionless, wouldn't there be an eletromagetic field generated, actually similar to a motor? Provided the mass of the two plates was sufficient, why couldn't the plates generate usable electricity (provided that coils were embedded in the plates such that the field potential could be captured). Would that not be a conversion of gravity to electrical energy?

Would this be possible?
 
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  • #2
No energy is generated. There is no heat. There aren't any motionless motors, really. You cannot convert gravity into electricity.

No, this is not possible.

When the magnets are far apart there is no potential energy in the magnetic fields due to the proximity of the magnets. When you lift one up, chemical potential energy leaves your muscles and goes into the gravitational field formed by the Earth and the magnet. When you lower the magnets together, some of this energy is released from the gravitational field and is transferred to the magnetic field between the two magnets. The original energy came from the sun and made food. You ate it and it went into your muscles. You moved the magnets around and the solar energy became magnetic field energy. The gravity field was only a temporary holding place for the energy while you were moving the magnets around. There was no energy to be extracted from gravity here.
 
  • #3
If there was a properly aligned coil between the two magnets then compressing the two magnets together would generate some amount of electricity. But as soon as the compression stopped, so that the magnets remained the same distance apart, then no more electricity would be produced.

This is actually more or less how a microphone works. The sounds make the coils compress around a magnetic which generate a small current that can be amplified and feed to a speaker. Yet once the coil stops moving, no matter how strong the magnet or compressed the field, there is no more power output. Power output depends on the change in field, not the field strength. A weight resulting from a gravitational field is a constant such that there is no variation resulting in a power output like with sound.
 

1. What is electromagnetic force?

Electromagnetic force is a fundamental force of nature that is responsible for the interactions between electrically charged particles. It is the force that holds atoms and molecules together, and is also responsible for the behavior of light and other electromagnetic radiation.

2. How does electromagnetic force work?

Electromagnetic force is mediated by particles called photons, which are the carriers of electromagnetic energy. When charged particles interact with each other, they exchange photons and this results in the force between them.

3. What are some examples of electromagnetic force in everyday life?

Some examples of electromagnetic force in everyday life include the attraction and repulsion between magnets, the operation of electronic devices such as cell phones and computers, and the behavior of light and other forms of electromagnetic radiation.

4. How does electromagnetic force differ from other fundamental forces?

Electromagnetic force is distinct from other fundamental forces, such as gravity and the strong and weak nuclear forces, because it is based on the exchange of particles (photons) rather than the exchange of force-carrying particles (like gluons for the strong force).

5. How is electromagnetic force important in the study of physics and other sciences?

Electromagnetic force plays a crucial role in the study of physics and other sciences as it helps to explain many natural phenomena, including the behavior of charged particles, the structure and behavior of atoms and molecules, and the properties of light and other forms of electromagnetic radiation.

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