Force between identical magnets

[labview1958]

The formula for the maximum force between identical magnets is:

 

F = AB^2/2mu where A = cross-section area of the magnet in m^2. I have taken out two identical magnets from the manufacturer pack rated at 1.23 Tesla.

 

I have found the Force by calculation to be 100N or can lift 10 kg. However the manufacturer pack says that one magnet can lift 4 kg. Is there a flaw in the formula or calculation?

[insane_alien]

wrong calculation is the problem. the equation you used was for 2 magnets attractin/repelling each other. you want an equation to work out the force on something that isn't a magnet

[Kedas]

http://www.answers.com/topic/magnet

[labview1958]

The magnets are rated at 1.23 Tesla. Should I use 1.23 Tesla or use this formula: B = mu(H+M) where H is 1.23T and M=0? Thus B=muH where H=1.23T, thus a much weaker B in my formula?