What is the equation for the force on a current-carrying wire in a magnetic field? What is the equation for the magnetic field generated by an air core coil? How can you use these two equations to help you solve this problem?
where B is flux density,L is lenght of conductor, and I is the current in the conductor.
magnetic field density=magnetic flux/c/s area
& reluctance=lenght of airgap/mew0 * c/s A
using f=BLI i found B=100T
next i used S=L/mew0*crosssectional area of air gap(L=10mm,c/sarea airgap=piD=3.14*0.001)
next using H=IN/L(I=100mA,N=50,L=15mm this assumed)
but when i go to find relative permeabilty i am getting a huge value which i think is wrong.
apart from that my understanding is that i there are three elements involved here ie the coil,the magnet,the airgap(am i right?)but how do i find the mmf of the magnet bcoz i cannot find the reluctance of the magnet