Math Core

Unit 5 · Test

Unit 5 test: Vector Calculus

15 questions. Answer them all, then submit to see your score. Solutions unlock after you submit.

This test covers vector fields, line integrals, the Fundamental Theorem for Line Integrals, Green's theorem, curl and divergence, parametric surfaces and surface integrals, Stokes' theorem, and the divergence theorem.

Question 1

Let F(x,y)=⟨x−y, xy⟩\mathbf{F}(x, y) = \langle x - y,\ xy\rangle. Find F(2,3)\mathbf{F}(2, 3).

Enter a point like (2, -3)

Question 2

Evaluate ∫C(x+2y) ds\displaystyle\int_C (x + 2y)\,ds, where CC is the segment from (0,0)(0, 0) to (6,8)(6, 8).

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 3

Find the work done by F(x,y)=⟨−y, x⟩\mathbf{F}(x, y) = \langle -y,\ x\rangle on a particle moving counterclockwise along the circle x2+y2=4x^2 + y^2 = 4 from (2,0)(2, 0) to (0,2)(0, 2).

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 4

Let F(x,y)=⟨2xy, x2+3y2⟩\mathbf{F}(x, y) = \langle 2xy,\ x^2 + 3y^2\rangle. Evaluate ∫CF⋅dr\displaystyle\int_C \mathbf{F}\cdot d\mathbf{r} along any path from (1,1)(1, 1) to (2,−1)(2, -1).

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 5

Which vector field on R3\mathbb{R}^3 is conservative?

Question 6

Use Green's theorem to evaluate ∮C(x2−2y) dx+(4x+y3) dy\displaystyle\oint_C (x^2 - 2y)\,dx + (4x + y^3)\,dy, where CC is the circle x2+y2=9x^2 + y^2 = 9, counterclockwise.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 7

Evaluate ∮Cx dy\displaystyle\oint_C x\,dy, where CC is the ellipse x24+y29=1\dfrac{x^2}{4} + \dfrac{y^2}{9} = 1, counterclockwise.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 8

Find div⁡F\operatorname{div}\mathbf{F} for F=⟨xy, yz, zx⟩\mathbf{F} = \langle xy,\ yz,\ zx\rangle.

Enter an expression, e.g. 3x^2 - 2x + 1

Question 9

Let F=⟨z, x2, y⟩\mathbf{F} = \langle z,\ x^2,\ y\rangle. Find curl⁡F\operatorname{curl}\mathbf{F} at (3,0,0)(3, 0, 0).

Enter a point like (2, -3)

Question 10

Which statement is true for every function ff with continuous second partial derivatives?

Question 11

Find the area of the part of the plane z=2x+2yz = 2x + 2y that lies above the unit disk x2+y2≤1x^2 + y^2 \le 1.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 12

Find the flux of F=⟨0,0,z⟩\mathbf{F} = \langle 0, 0, z\rangle upward through the part of z=1−x2−y2z = 1 - x^2 - y^2 above the xyxy-plane.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 13

Let F=⟨−y, x, z⟩\mathbf{F} = \langle -y,\ x,\ z\rangle and let SS be the part of z=9−x2−y2z = 9 - x^2 - y^2 with z≥0z \ge 0, oriented upward. Use Stokes' theorem to evaluate ∬Scurl⁡F⋅dS\displaystyle\iint_S \operatorname{curl}\mathbf{F}\cdot d\mathbf{S}.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 14

Use the divergence theorem to find the outward flux of F=⟨x3, y3, z3⟩\mathbf{F} = \langle x^3,\ y^3,\ z^3\rangle across the sphere x2+y2+z2=4x^2 + y^2 + z^2 = 4.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 15

Find the outward flux of F=⟨x, y2, z3⟩\mathbf{F} = \langle x,\ y^2,\ z^3\rangle across the boundary of the cube 0≤x,y,z≤10 \le x, y, z \le 1.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.