PHYS 2426 501 Spring 2016 Chapter 28 Question 2 Question 2 A

PHYS 2426 501 Spring 2016 Chapter 28 Question 2 Question 2 A 15.0 m-long copper wire, 2.10 mm in diameter including insulation, is tightly wrapped in a single layer with adjacent coils touching, to form a solenoid of diameter 3.00 cm (outer edge).

Solution

Each loop of wire is d long = *3.00cm = 9.42cm = 0.0942m

So the wire is 15.0m long so it can make 15/0.0942 = 159 loops

So the solenoid is 2.0mm*159 = 318mm or 31.8cm long

So now there are 159turns/0.318m = 500 turn per meter

Now the B field at the center is µo*n*i = 4x10^-7*500*15 = 9.45x10^-3T