Honors

The assignment for tonight is two pronged, firstn plasma confinement; second lab :

I) Plasma physics:
1. Find the magnetic force per m of length on a plasma with a current of 8 million amps flowing in a magnetic filed with B = 6.5 T

2. Find the the pressure gradient ( Delta P/delta r) in a plasma whose central temperature is 150 million degrees and which has 5x10^19 nuclei per m^3. Assume that the pressure falls off uniformly from the center to near zero at the plasma edge which is 3.5 m from the center. remember P = (N/Vol) kT

3. For the plasma in 2, what is the current density, J (amps/m^2), required to balance the pressure gradient if B = 7 T.

II) Resonance:

1. The distance between a free end and a fixed end for the first ( fundamental) resonance or harmonic is what fraction of a wavelength? Draw a simple sketch.

2. The time for wave to travel from the free end to the fixed end and back to the free end in problem 1 is what fraction of a period?

3. To get a resonance again for the same frequency and wave speed as in the first casewith a longer tube, the length between the free end and the fixed of the new, longer tube must be must be_____ times the length of first tube.