Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

1. (10 points) Which of the following is not true of vector fields? A. Each poin

ID: 1778176 • Letter: 1

Question

1. (10 points) Which of the following is not true of vector fields? A. Each point in space has a corresponding vector B. The gradient of a scalar field produces a vector field C. The Electric field can be represented as a vector field D. The magnitude of the vector field decreases radially outward from a point charge. E. The Electric Potential field can be represented as a vector field 2. (10 points) What is the magnitude of the electric field midway between a dipole located on the X axis with a positive charge q at -and a negative charge, -q, located at 2 Express in terms of the dipole charge q, and the dipole separation distance d? B. 2 C.-2 D. 4 di di 3. (10 points) Which charge arrangement will produce the greatest magnitude (positive or negative) of electric field in the center? A. Two equal dipoles, with charges located a distance d from the origin on the X and Y axes receptively. B. Four equal positive charges located a distance d along each axis C. Four equal negative charges located a distance d along each axis D. All of the above produce an equal non-zero magnitude E. All of the above produce an equal magnitude that is exactly zero

Explanation / Answer

1)
A) True
Each position in space can be associated with a vector called position vector.

B) True.
For an example, the gradient of electric potential (scalar) is electric field, which is a vector.

C) True
Electric field is a vector, which follows all rules of vector algebra.

D) True
Since the magnitude is inversely proportional to the square of the distance, magnitude decreases.

E) False
Electric potential is a scalar.

2)
Electric field due to +q located at - d/2 is
E1 = Kq/(d/2)2 towards right
= 4 Kq/d2                  [Towards right is positive]
Electric field due to -q located at + d/2 is
E2 = 4 Kq/d2 towards right

Total electric field at the midpoint is
E = E1 + E2 = 8 Kq/d2
None of the options are correct

3)
Correct answer is option A.
Only in the case of dipole, there is non-zero electric field at the center