A vector field assigns a vector to every point in a region of space.
07 Vector Fields Online Quiz Questions
Use this free practice quiz with 20 questions to review 07 Vector Fields, test your knowledge, and prepare for your next test or exam.
For the conservative field F(x,y)=⟨2xy+3,x2+4y⟩, a potential function is f(x,y)=x2y+3x+2y2. What is the work along any path from A=(0,1) to B=(2,3)?
For a two-dimensional velocity field v=⟨P(x,y),Q(x,y)⟩, a streamline satisfies dxdy= when .
If F=∇f, what does the Fundamental Theorem for Line Integrals imply about ∫CF⋅dr?
- A
The value depends on the length of the path.
- B
The value depends only on the initial and terminal points.
- C
The value is always zero, even when the endpoints differ.
- D
The value depends only on the speed used to parametrize the path.
A streamline of a time-dependent velocity field necessarily traces the path followed by one specific fluid particle over time.
- A
True
- B
False
Select all conditions that must hold for a three-dimensional field F=⟨P,Q,R⟩ to pass the cross-partial test for conservativeness.
- A
Py=Qx
- B
Px=Qy
- C
Pz=Rx
- D
Qz=Ry
- E
Px=Rz
What adjective describes a vector field whose curl is zero?
For a fluid velocity field, positive divergence indicates local , whereas negative divergence indicates local .
Which function is a potential function for F(x,y)=⟨2xy+3,x2+4y⟩?
- A
f(x,y)=x2y+3x+2y2
- B
f(x,y)=2x2y+3x+4y2
- C
f(x,y)=x2y+3y+2x2
- D
f(x,y)=x2+3x+2y2
Select all statements supported by the vector-calculus interpretation of a fluid velocity field.
- A
A flow with zero divergence is modeled as incompressible.
- B
Positive divergence indicates local expansion or source-like behavior.
- C
Zero divergence guarantees that the flow has zero curl.
- D
Zero curl indicates no local rotational tendency.
Explain why checking that the curl is zero is not, by itself, enough to conclude that a vector field is conservative. State the domain condition that makes the test sufficient and describe what can go wrong when the domain has a hole.
Which statement correctly relates a conservative force F, potential energy U, and the work W done as a particle moves from A to B?
- A
F=∇U and W=U(B)−U(A)
- B
F=∇U and W=U(A)−U(B)
- C
F=−∇U and W=U(A)−U(B)
- D
F=−∇U and W=U(B)−U(A)
Let F(x,y)=⟨x2+3y,3x+4y2⟩ on all of R2. Which conclusion is justified?
- A
It is not conservative because Py=Qx.
- B
It is conservative because Py=Qx and the domain is simply connected.
- C
It is not conservative because the field has two components.
- D
It is conservative only if P=Q.
A conservative vector field has potential function f(x,y)=x2+y2. What is the line integral from A=(1,0) to B=(0,2), regardless of the path?
- A
−3
- B
1
- C
3
- D
5
True or false: In a time-dependent fluid velocity field, a streamline necessarily gives the path traced by one particular fluid particle.
- A
True
- B
False
Compute the divergence of F(x,y,z)=⟨x2y,yz,z2x⟩.
- A
x2+y2+z2
- B
2xy+yz+2zx
- C
x2y+yz2+zx2
- D
2xy+z+2zx
What term describes a vector field whose curl is zero?
Find one potential function for F(x,y)=⟨2xy+3,x2+4y⟩.
- A
x2y+3x+2y2
- B
2x2y+3x+4y2
- C
x2+3xy+2y2
- D
x2y+3y+2x2
For the planar velocity field v(x,y)=⟨−y,x⟩, what is the exact scalar curl Qx−Py?
A conservative force has potential energy U(x,y)=x2+y2. What work does the force do when an object moves from A=(0,3) to B=(0,2)?
- A
−5
- B
5
- C
13
- D
36