A laboratory arrangement consists of a long solenoid coaxially surrounded by a pair…
PHYSICS · Multi-part · AP · Physics 2: Algebra-based · Magnetism and Electromagnetism · Magnetism and Electromagnetism
Problem
A laboratory arrangement consists of a long solenoid coaxially surrounded by a pair of identical circular coils (Helmholtz coils). The solenoid produces a magnetic field Bs along its axis, while the coils produce a field Bh along the same axis but in the opposite direction.
(i) State the principle of superposition of magnetic fields.
(ii) Explain qualitatively how the resultant magnetic field inside the solenoid can be varied smoothly from a positive value through zero to a negative value without changing the physical dimensions of the apparatus.
(iii) Mention any two practical advantages of employing such field adjustment in precision experiments.