Copper & Magnets: Generating Repulsive Force

[zepp0814]

Hi so I am aware that when copper is introduced to a magnetic field it will generate it's own that repels the field inducing it, this repulsive force is weak but how strong of a magnetic field would it take to generate a considerable amount of force on the copper

 

[zepp0814]

Also is there a formula to find the relationship between the strength of the magnet (electromagnet) and the repulsive force on the copper.