Explaining the Repulsion of an Electromagnet on Metals

In summary, the conversation discusses the possibility of an electromagnet repelling an iron block. The author explains that this is only possible if the iron block is magnetized, and with other conductive metals like aluminum, it can be pushed away due to eddy currents. The author also provides other interesting facts about the demonstration, including the use of a transformer from a microwave oven and the author's location in Zaragoza, Spain.
  • #1
akashverma
34
0
Can it be possible that an electromagnet would repel a iron block?? if yes then please explain.
 
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  • #2
Only if the iron block is magnetized.
 
  • #3
Integral said:
Only if the iron block is magnetized.
according to me the iron block will be magnetized by the field of electromagnet in such a way that it will attract it and if there is no external field then how will it be possible that an electromagnet repels an iron block??
I saw a video on youtube where electromagnet repels an iron block without any external field.
 
  • #4
akashverma said:
according to me the iron block will be magnetized by the field of electromagnet in such a way that it will attract it and if there is no external field then how will it be possible that an electromagnet repels an iron block??
I saw a video on youtube where electromagnet repels an iron block without any external field.

If you notice, the electromagnet attracted the iron hammer.
The silver cylinder and slab are aluminum, as stated in the comments section by the author.

The author's explanation:

http://www.youtube.com/profile_redirector/103932266793618344395
21 hours ago
Why can it also push of metal things? And on what does it depend if it pull in or push of?

http://www.youtube.com/profile_redirector/111021059413939523708[the author]
20 hours ago

With ferromagnetic metals, always attractive (pull).

With other conductive metals (copper, aluminum) push, because of eddy currents.

The electromagnet generates a magnetic field. That magnetic field induces a current on the metals that are near. If the metal is open that currents only will flow in small local circles, but if you close the ring the current will flow around the hole ring. That current will generate a magnetic field, because moving charges generate magnetic fields (Oersted, Ampere) and that magnetic field opposes to the former one, the one from the electromagnet (Lenz's Law). This is why the ring is repelled.​

Other facts from the comments section:
This is a transformer from a microwave oven.
The author powered the coil with 240 vac.​

Interesting demonstration. I've only ever seen static magnets used to demonstrate this effect.

The author, according to their twitter account, is from Zaragoza, Spain.
"DIY, science, technology, experiments, physics, chemistry, ETC"​

I like that guy. Someone should invite him to PF. :)
 
  • #5
OmCheeto said:
If you notice, the electromagnet attracted the iron hammer.
The silver cylinder and slab are aluminum, as stated in the comments section by the author.

The author's explanation:

http://www.youtube.com/profile_redirector/103932266793618344395
21 hours ago
Why can it also push of metal things? And on what does it depend if it pull in or push of?

http://www.youtube.com/profile_redirector/111021059413939523708[the author]
20 hours ago

With ferromagnetic metals, always attractive (pull).

With other conductive metals (copper, aluminum) push, because of eddy currents.

The electromagnet generates a magnetic field. That magnetic field induces a current on the metals that are near. If the metal is open that currents only will flow in small local circles, but if you close the ring the current will flow around the hole ring. That current will generate a magnetic field, because moving charges generate magnetic fields (Oersted, Ampere) and that magnetic field opposes to the former one, the one from the electromagnet (Lenz's Law). This is why the ring is repelled.​

Other facts from the comments section:
This is a transformer from a microwave oven.
The author powered the coil with 240 vac.​

Interesting demonstration. I've only ever seen static magnets used to demonstrate this effect.

The author, according to their twitter account, is from Zaragoza, Spain.
"DIY, science, technology, experiments, physics, chemistry, ETC"​

I like that guy. Someone should invite him to PF. :)
Got the point.. thank you man and this setup is one of the tremendous setup i have ever watched.
 

1. What is repulsion by an electromagnet?

Repulsion by an electromagnet is a phenomenon in which two objects with opposite magnetic poles will push away from each other when in close proximity. This is caused by the magnetic field created by the electromagnet.

2. How does an electromagnet create repulsion?

An electromagnet creates repulsion by using an electrical current to generate a magnetic field. The strength and direction of the magnetic field can be controlled by adjusting the amount of current flowing through the electromagnet. When two objects with opposite poles are brought close to the electromagnet, the magnetic fields will interact and cause repulsion.

3. What are some practical applications of repulsion by an electromagnet?

Repulsion by an electromagnet has many practical applications, such as magnetic levitation trains, magnetic bearings for rotating machinery, and magnetic separators for separating metals in recycling processes. It is also commonly used in scientific experiments and demonstrations to showcase the properties of magnets.

4. Can the strength of repulsion be adjusted in an electromagnet?

Yes, the strength of repulsion in an electromagnet can be adjusted by changing the amount of current flowing through it. Increasing the current will increase the strength of the magnetic field and therefore increase the repulsion between objects with opposite poles.

5. Are there any safety concerns when working with repulsion by an electromagnet?

Yes, there are some safety concerns when working with repulsion by an electromagnet. The strength of the magnetic field can be strong enough to cause injury or damage to electronic devices. It is important to handle electromagnets with caution and follow proper safety protocols when using them.

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