1. if the magnetic field is 2.1 m from a current carrying wire is 7.1x10^-5 T, what is the current flowing through the wire?

2. The electromagnet in an MRI has a magnetic field of 2.5 T. If there are 100 A of current running through the magnet, how many turns are there in a 1.8 m length?

1 answer

1. standard formula:
B=mu*I/2PIr solve for I.

1. standard formula:
http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/solenoid.html#c2
B=mu*N*L