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- Jan 7, 2012
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So, I was doing some prep with TPR online material and I came across this Question:
As the charges are brought from the earth to the sphere where is the electrical force on the charges the greatest?
A.
At the bottom of the conveyor belt
B.
On the conveyor belt just outside the sphere
Correct Answer
C.
In the middle of the sphere
D.
On the surface of the sphere
Explanation:
B. Choices C and D can be eliminated because the electric field is zero inside the sphere and on the surface of the sphere which is a conductor. From the equations and passage information, the electric field is stronger closer to the sphere so choice B is correct.
The diagram the question references is attached.
The answer explanations says that the electric field is zero inside the sphere and on the surface of the sphere, which is a conductor. I understand why it is zero inside the sphere, but why is the electric field zero on the surface of a conductor? I thought conductors had evenly distributed charge on the surface, and since E=KQ/(r^2), you should have an electric field at the surface?
As the charges are brought from the earth to the sphere where is the electrical force on the charges the greatest?
At the bottom of the conveyor belt
On the conveyor belt just outside the sphere
Correct Answer
In the middle of the sphere
On the surface of the sphere
Explanation:
B. Choices C and D can be eliminated because the electric field is zero inside the sphere and on the surface of the sphere which is a conductor. From the equations and passage information, the electric field is stronger closer to the sphere so choice B is correct.
The diagram the question references is attached.
The answer explanations says that the electric field is zero inside the sphere and on the surface of the sphere, which is a conductor. I understand why it is zero inside the sphere, but why is the electric field zero on the surface of a conductor? I thought conductors had evenly distributed charge on the surface, and since E=KQ/(r^2), you should have an electric field at the surface?
