Physics · Electrostatics
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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 x106 N/C. If the test charge is replaced with another test charge of 13 μC, what happens to the external electric field at P?
- A
It remains the same
- B
It reverses direction
- C
It changes in a way that cannot be determined
- D
3.1 x 105 N/C
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.
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.
Incorrect as per formula
Incorrect as per formula
Incorrect as per formula
Tagged under Physics · Electrostatics · 2021