A long straight wire runs along the axis of a long solenoid having turns per metre
MATHEMATICS · Single correct · ISC · Physics · Electromagnetic Induction and Alternating Currents · Magnetic Effects of Current and Magnetism
Problem
A long straight wire runs along the axis of a long solenoid having 1000 turns per metre. A point inside the solenoid is 2.0cm from the wire. If the current in the straight wire is 10A, what current should flow through the solenoid so that the magnetic fields produced at the point by the wire and by the solenoid have equal magnitudes?
(a) 0.8\,\text{A}
(b) 0.08\,\text{A}
(c) 8\,\text{A}
(d) 0.008\,\text{A}