# Determine the magnetic field just inside the wall.

The magnetic field created by a large current passing through plasma (ionized gas) can force current-carrying particles together. This pinch effect has been used in designing fusion reactors. It can be demonstrated by making an empty aluminum can carry a large current parallel to its axis. Let R represent the radius of the can and I the current, uniformly distributed over the can's curved wall.

(a) Determine the magnetic field just inside the wall. (Use any variable or symbol stated above along with the following as necessary: μ0.)
 magnitude B = direction

(b) Determine the magnetic field just outside. (Use any variable or symbol stated above along with the following as necessary: μ0 and π.)
 magnitude B = direction

(c) Determine the pressure on the wall. (Use any variable or symbol stated above along with the following as necessary: μ0 and π.)
 magnitude P = direction

asked Feb 19, 2012 in Physics

Steps will be posted shortly, but answers are:

Part A: Magnitude B = 0, no direction

Part B:

Direction:  tangent to the wall

Part C:

Direction: inward

answered Feb 25, 2012 by ~Expert~ (1,318 points)
selected Feb 25, 2012 by awesome