A current I flows in a long thin walled cylinder of radius R. What pressure do the walls of the cylinder experience?
The magnetic field outiside the cylinder is μ0I2×2πR
The magnetic fied inside the cylinder is 0
The magnetic field in the inside the conductor is the average of the above two =μ0I4×2πR
The current through a small strip of width dl is given by Idl2πr
Hence, the force acting on it given by F=BiL=μ0I4×2πRIdl2πrL
The area of the strip is given by A=Ldl
Hence the pressure on the strip is given by FA=μ0I28π2R2