A Long Narrow Solenoid Has Length ℓ and a Total

Multiple Choice

A long narrow solenoid has length ℓ and a total of N turns, each of which has cross-sectional area A.Its inductance is:

A) µ₀N²Aℓ
B) µ₀N²A/ℓ
C) µ₀NA/ℓ
D) µ₀N² ℓ/A
E) none of these