Physics 1122 Spring, 2026 Exam #1
Short-Answer Questions. Choose the closest answer and use the bubble sheet.
Each multiple-choice question is worth 5 points, for a total of 30 points on this part of the quiz.
S1. The figure shows two positively charged 5.0 g spheres suspended from two very thin L =
1.0 m long threads. The spheres repel each other after being charged to the same charge q and
hang at rest as shown. The angle θ is 4.1o. What is the charge on each sphere?
a) 7.1 x 10-7 C
b) 3.6 x 10-7 C
c) 1.8 x 10-7 C
d) 8.9 x 10-8 C
e) 4.5 x 10-8 C
S2. Two Gaussian spheres surround equal charges as shown. The radius of sphere B is greater
than sphere A. Which of the following statements are true?
I. The electric field is weaker at B than at A. Since flux depends on electric field
strength, the flux through B is less than the flux through A.
II. The surface area is greater at B than at A. Since flux depends on surface area, the
flux through B is greater than the flux through A.
III. The flux through sphere A and B are equal because they enclose equal charges.
A. I
B. II
C. III
D. None of these
E. More than one of these
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Short-Answer Questions. Choose the closest answer and use the bubble sheet.
Each multiple-choice question is worth 5 points, for a total of 30 points on this part of the quiz.
S1. The figure shows two positively charged 5.0 g spheres suspended from two very thin L =
1.0 m long threads. The spheres repel each other after being charged to the same charge q and
hang at rest as shown. The angle θ is 4.1o. What is the charge on each sphere?
a) 7.1 x 10-7 C
b) 3.6 x 10-7 C
c) 1.8 x 10-7 C
d) 8.9 x 10-8 C
e) 4.5 x 10-8 C
S2. Two Gaussian spheres surround equal charges as shown. The radius of sphere B is greater
than sphere A. Which of the following statements are true?
I. The electric field is weaker at B than at A. Since flux depends on electric field
strength, the flux through B is less than the flux through A.
II. The surface area is greater at B than at A. Since flux depends on surface area, the
flux through B is greater than the flux through A.
III. The flux through sphere A and B are equal because they enclose equal charges.
A. I
B. II
C. III
D. None of these
E. More than one of these
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