## College Physics (4th Edition)

The solenoid should have $2.2\times 10^4$ turns.
We can find the required number of turns $N$ in the solenoid: $B = \frac{\mu~N~I}{L}$ $N = \frac{B~L}{\mu~I}$ $N = \frac{(1.5~T)(1.5~m)}{(4\pi \times 10^{-7}~T~m/A)(80~A)}$ $N = 2.2\times 10^4$ The solenoid should have $2.2\times 10^4$ turns.