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Question #42843
The Question
In a region of space, two independent static electric potentials are established, given by: where is a positive constant with units of , and is a positive constant with units of meters. The corresponding electric fields are and . A new vector field is defined as . What is the magnitude of the flux of through the open hemispherical surface defined by with ?
Options
- A.
- B.
- C.
0
- D.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Multi-Concept_Bridge
Master problems that require linking physics and math concepts to solve complex competitive questions.
Concepts Behind This Question
Flux and Surface Geometry|Conservative Field Path Independence|Gradient Operator
Why This Question Is Tricky
Common Mistakes
This problem tests the student's ability to recognize that the cross product of two conservative fields (electrostatic fields) has zero divergence.
The primary trap is attempting a 'brute force' surface integration of the vector field over the hemispherical surface.
Due to the Gaussian exponential term, this integral appears analytically intractable, causing students to either guess zero or waste significant time.
By applying Gauss's Divergence Theorem (or alternatively, Stokes' Theorem), the student can bypass the complex geometry and evaluate the flux over the flat circular base, where the fields simplify to uniform vectors.
Quick Facts About This Question
Question Information
| Subject | Physics |
| Chapter | Electric Charges and Fields - Class 12 |
| Concept | Flux and Surface Geometry |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |