Magnets attract and oppose, right?

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In summary, perpetual motion machines are not possible due to the laws of thermodynamics and the fact that magnets are not power sources. The force of a magnet can be compared to a balloon on a stick, where the initial force must come from an external source. While magnets can create movement, they cannot sustain it indefinitely without the input of energy. Therefore, it is not possible to create an engine that requires no wires, no copper, no batteries, capacitors, resistors, or any electricity whatsoever. The concept of perpetual motion machines is a banned topic on this forum, as it goes against the principles of science and is not reproducible or testable.
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magnertia
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then why has no one built an engine that requires no wires, no copper. no batteries, capacitors, resistors, no electricity whatsoever? if a magnet is strong enough it can push or pull something, right? then why aren't wheels magnetic? generators, engines, rotors, hard drives...why is electricity necessary if magnetic fields already make things move?
 
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Because magnets are not power sources. You're converting potential energy to kinetic energy and vise versa.

Think of the repelling force of a magnet as a balloon on a stick (because that's really what it acts like). You can push against the balloon and get it to push back, but it's only because of the force you initially put into it.

Think of the attracting force as just gravity. You can climb up onto a chair and jump off and yes gravity will pull you down, but without using energy for your initial effort of climbing onto the chair you wouldn't have been able to get that conversion of gravitational potential energy into kenetic energy moving you downwards.

Now if we put these forces together to try for perpetual motion we get something like you dropping a ball onto a trampoline, sure you will get an oscillation (the bouncing of the ball) for a period of time but eventually it will find equilibrium and movement will come to a stop.
 
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magnertia said:
then why has no one built an engine that requires no wires, no copper. no batteries, capacitors, resistors, no electricity whatsoever? if a magnet is strong enough it can push or pull something, right? then why aren't wheels magnetic? generators, engines, rotors, hard drives...why is electricity necessary if magnetic fields already make things move?

Welcome to the PF.

Perpetual motion machines are on the PF "Banned Topics" list, as described in the Rules link at the top of the page. You can read through the linked, locked threads quoted below for more information on why PMMs are not possible.

Rules said:
Perpetual motion and "free energy" discussions

Search PF and you will find many threads that have been closed in a number of forums. As for S&D, any claim of this nature would be reproducible and/or testable by the scientific community; hence there is no need for debate.
EDIT by berkeman -- here are some recent locked PMM threads:
https://www.physicsforums.com/showthread.php?t=522548
https://www.physicsforums.com/showthread.php?t=520290
https://www.physicsforums.com/showthread.php?t=7735
https://www.physicsforums.com/showthread.php?t=515402
https://www.physicsforums.com/showthread.php?t=403572
 

1. How do magnets attract and oppose?

Magnets have two poles, a north pole and a south pole. Opposite poles (north and south) attract each other, while like poles (north and north or south and south) repel each other. This is due to the magnetic fields that surround the magnets.

2. Why do magnets attract certain materials?

Materials that contain iron, nickel, or cobalt are attracted to magnets because they have magnetic properties. These materials have their own magnetic fields that align with the magnetic field of the magnet, causing them to be pulled towards the magnet.

3. Can magnets attract non-metal objects?

Yes, magnets can attract non-metal objects such as plastic or wood. However, these materials do not have magnetic properties and are not attracted to magnets. Instead, the magnet is attracted to the small amount of iron particles present in these materials.

4. Do magnets always attract or oppose each other?

No, magnets can also cancel each other out. When two magnets with opposite poles are placed close to each other, their magnetic fields can cancel each other out, resulting in no attraction or repulsion.

5. How can magnets be used in everyday life?

Magnets have various uses in our daily lives, such as in electric motors, generators, and speakers. They are also used in household items like refrigerator magnets, magnetic toys, and magnetic jewelry clasps. Magnets are also important in medical equipment like MRI machines and in transportation systems like maglev trains.

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