Solenoid a has length l and n turns, solenoid b has length 2l and n turns, and solenoid c has length l/2 and 2n turns. if each solenoid carries the same current, rank the magnitudes of the magnetic fields in the centers of the solenoids from largest to smallest. (use only "> " or "=" symbols. do not include any parentheses around the letters or symbols.)
which is correct?
a. b, c, ab. c, a, bc. c, b, ad. a, c, be. a, b, c