Question

For a long solenoid of length \[l\] with \[N\] total turns, what is the number of turns per unit length?

Options

• \[n=Nl\]

• \[n=\frac{N}{l}\]

• \[n=\frac{l}{N}\]

• \[n=\frac{N}{A}\]

Answer 1

Turns per unit length means total turns divided by solenoid length. Thus \[n=\frac{N}{l}\], or equivalently \[N=nl\].