Solenoid Magnetic Field Help

[pat666]

Homework Statement

You have 12m of 0.50mm diameter copper wire and a power supply capable of passing 17A through the wire.
a)What magnetic field strength would you obtain inside a 2.0cm diameter solenoid with the wire spaced as closely as possible?
b)What magnetic field strength would you obtain at the center of a single circular loop made from the wire?

Homework Equations

B=u₀nI
B=u₀I/2r

The Attempt at a Solution

a) n=pi*0.002=0.00628 or n=12/.00628=1909.86 not sure on this
B=4pi*E-7nI B=1.34*10⁷⁶T or B=4.08*10^-2
b) B=4piE-7=17/(2*.001)=1.1^-3T


b is definitely wrong but I don't know why and I am completely unsure on a.
all help appreciated.

 

[rl.bhat]

Homework Statement

You have 12m of 0.50mm diameter copper wire and a power supply capable of passing 17A through the wire.
a)What magnetic field strength would you obtain inside a 2.0cm diameter solenoid with the wire spaced as closely as possible?
b)What magnetic field strength would you obtain at the center of a single circular loop made from the wire?

n = 12/π*0.0205

Radius of the single loop = R = 12/2π

 

[pat666]

thanks for that, do you know what's wrong with a?