Solenoid #1 has a length L, cross-sectional area A, and N turns. Solenoid #2 has a length 2L, cross-sectional area 2A, and 2N turns. Which long solenoid has the greater magnetic field at its center when equal currents are going through them?
A) Both have the same magnetic field.
B) #1
C) #2
D) Since it depends on the values of A and L, none of the above are correct.

Question

Quizplus · Accepted Answer

The magnetic field inside a long solenoid is given by B = μ₀ * (N/L) * I, where N is the number of turns, L is the length, and I is the current. For both solenoids, the ratio N/L is the same (N/L for #1 and 2N/2L for #2), so they have the same magnetic field at their centers when equal currents are applied.

Solenoid #1 Has a Length L, Cross-Sectional Area A, and N