Calculate magnet repulsive force?
I'm looking to make a "floating" model by insetting NdFeB rare-earth magnets with same poles facing so they repel. Now, magnet selling places specify the "pull" a magnet might have, say 1.2kg.
What I would like to know is if the repel is equal in magnitude as the pull if two similar magnets are placed with same poles facing, is the force exerted 1.2kg and so I could float 1.2kg of stuff? Also, does stacking magnets double the attractive or repelling force, i.e. do two 1.2kg magnets stuck together lift 2.4kg of stuff, negating the small difference in distance of one magnet from the object? Is there a way to calculate the distance between two opposing magnets with a force applied. Does it follow the inverse cube rule?
And if the stacking does work, do I also need an equal number of magnets on the other side for repelling, i.e. a stack of two 1.2kg magnets repels 2.4kg with one 1.2kg on the other side, or not? Does the magnet on the other side have to be the same force?
Lots of questions but hoping someone can shed some light on this as I've not been able to find anything about it :-(