A charge q is placed at the center of a neutral conducting spherical shell of inner radius a and outer radius b. The electric field at a point r > b is:
Correct answer: A. kq/r²
- A. kq/r²
- B. Zero
- C. kq/(r² - a²)
- D. kq/(b - A)
Explanation
For r > b, the conducting shell's induced charges make it appear as if all charge q is at the center. Thus, E = kq/r², as for a point charge.
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