Fredag 8/3 i FUF-lokalet! .
Magnetostatics. Amperes law. Biot-Savarts law. Lorentz force. Magnetic flux.
Read Chapter 29 in Ohanian 3rd ed and prepare for the checkup questions.
We are going to use Biot-Savarts law in a
number of examples and exercises. I expect you to have solved the first
two at home being able to exhibit at the blackboard.
1) The B-field
surrounding a long straight wire carrying a current I.
2) The B-field
on the z-axis of a circular current loop in the x,y-plane having a radius R and center in (0,0,0).(Ohanian exercise 60)
3) Find
the B-field at a point P on the z-axis of a cylindrical coil of finite
length L consisting of N windings and with a current I. Hint: Make an
integration using the preceding result. Use as integration variable the
angle under which the individual loops are seen from P (exercise 62)
4) In
a thin plate of width b but infinite length a current I is flowing
uniformly distributed across the plate. Find the B- field in a point P
above the midle of the plate (exercise 41). Compare with the electric
field of a charged plate.
5) A
current is running along the axial direction on a cylindrical surface
equally distributed over it. What is the B-field outside the cylinder?
What is the B-field inside the cylinder.