A test charge of 23 μC is at a point P where an external electric field is directed to the left and has a magnitude of 3.1 x 10^6 N/C. If the test charge is replaced with another test charge of 13 μC, what happens to the external electric field at P?
Correct answer: A. It remains the same
- A. It remains the same
- B. It reverses direction
- C. It changes in a way that cannot be determined
- D. 3.1 x 10^5 N/C
Explanation
The presence of the test charge at point P does not affect the external electric field because it is much smaller than the source charges and does not produce a significant electric field. We can also see it mathematically as we can express the electric field at a point P as: E = F/Q Now when charge (Q) is replaced with a smaller charge, the force acting on it also decreases and the Electric Field (E) acting on it remains the same. Therefore, the correct option is A) It remains the same.
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