# Mass disipation when using magnets

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Hello everyone,

First time poster here.

My question is..."When using a magnet to levitate a object (Magnetic levitation) what is the downward force on the bottom magnet?

Example: If I had a 1kg magnet and was able to push it vertically using another magnet, and it didn't slide off, what would the downward force be? half of the weight being lifted + gravity?

Edited by Maninga
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The forces on the bottom magnet are gravity (its weight) and the magnetic force from the upper magnet. So what is the magnetic force from the upper magnet?

(Hint: is it accelerating?)

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The forces on the bottom magnet are gravity (its weight) and the magnetic force from the upper magnet. So what is the magnetic force from the upper magnet?

(Hint: is it accelerating?)

Ok so it's Gravity (bottom weight) + Magnetic push (top weight)

I would assume the force between the two magnets would come to a balanced state once the optimum distance apart is reached. Depending on the force of the top magnet, being an unknown variable as I have no way to measure it.

Hypothetical experiment...If you put the bottom magnet on a scale and got the weight, say for arguments sake 100grams, and then you put the top magnet above (and it didn't slip off) and let them push each other away till both magnetic pushing forces came to a natural balance and the top magnet was perfectly levitated, would the weight recorded on the scale be the original weight of the first magnet plus the full weight of the second? or would it be the bottom magnets weight + magnetic down force which I would assume would be the same as the magnet ontop.

Edited by Maninga
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Ok so it's Gravity (bottom weight) + Magnetic push (top weight)

I would assume the force between the two magnets would come to a balanced state once the optimum distance apart is reached. Depending on the force of the top magnet, being an unknown variable as I have no way to measure it.

Hypothetical experiment...If you put the bottom magnet on a scale and got the weight, say for arguments sake 100grams, and then you put the top magnet above (and it didn't slip off) and let them push each other away till both magnetic pushing forces came to a natural balance and the top magnet was perfectly levitated, would the weight recorded on the scale be the original weight of the first magnet plus the full weight of the second? or would it be the bottom magnets weight + magnetic down force which I would assume would be the same as the magnet ontop.

As you say, the the magnetic down force is the same as the weight of the upper magnet — the system is not accelerating, so the magnetic force on each magnet is equal in magnitude (Newton's 3rd law) and the upper magnetic force is equal to the weight, because the net force is zero (Newton's second law)

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the second video has the most description.

Quantum Levitation

Quantum Levitation

Edited by krash661

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