MTH 255 Sample Midterm 2

This was the second midterm given by another instructor.

1.
In this problem the curve C is the quarter of the circle of radius 2, centered at the origin, which lies in the first quadrant, oriented from (2,0) to (0,2).
(a)
Compute the integral along C of f ds, where f(x,y) = xy/(x2+y2).
(b)
Compute the integral along C of F · dr for F = y i-x j.

2.
In this problem C is the half of the circle x2+y2 = 9 in the right half plane (x > 0) together with the segment on the y-axis from (0,3) to (0,-3) oriented counterclockwise, and F = -x2y i+xy2 j.
(a)
Compute the integral along C of F · dr.
(b)
Compute the integral along C of F · Nds, where N is the outer unit normal.

3.
Compute the integral along C of F · dr where F = grad((x+2y+3z)exz) and C is the piecewise smooth curve consisting of the straight line segments from (0,1,1) to (1,2,1) to (2,1,0).

4.
Let F = (3y2-3x2+y) i+(6xy+x+z) j+y k.
(a)
Compute curl F.
(b)
Compute div F.
(c)
Is F conservative (everywhere)? Justify your answer.

5.
(This question deals with material we have not covered.)
(You can download the solutions (in PDF format), but please try the problems without peeking first.)