Differential elements and line integral	Jan. 31, 2007


+ For a system with [equation] ,
[equation]
[equation] , [equation] , [equation]
dV = [equation] .

+ Line integration (Examples 3.2 & 3.9): [equation] which measures circulation when the path is closed, i.e. [equation] . Steps:
1) find [equation]
2) find equations of the path (line). May be in pieces.
3) substitute the equations of the lines into [equation] and set the limits of integration.

+ General method for evaluating line integral, [equation] :
Parametric equation for a line, e.g. in (x,y,z)
x=f(t), y=g(t), z=h(t)
Calculate [equation]
[equation]
Example 1.11: Line integration

Example 1.12: Ampere's Law
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HW #4	due 2/6/07


1. Find (i) [equation] and (ii) P.2-12 (c) (in my notation [equation] ) and (e) (in my notation [equation] ) only (p. 68).
2. Identify the number of surfaces, equation for each surface, normal and scalar differential surface element of each surface for the volume described by [equation] , [equation] , [equation] , i.e. half of a cylinder sliced along z axis.
3. (a) identify the differential surface area [equation] and determine the area of the following surface: [equation] , [equation] (hemisphere), (b) identify the differential volume [equation] and calculate the volume of the following object: [equation] , [equation] , [equation] .
Extra-credit
An electric field intensity [equation] in air passing through a cylinder of radius [equation] . Find a) [equation] at P=(2, [equation] , 2), b) the scaler component of [equation] that is normal to the cylindrical (curve) surface at point P.


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Last Modified: January 27, 2007
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