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Four point charges of same magnitude () are placed at four corners of a rigid square frame as shown in figure. The plane of the frame is perpendicular to -axis. If a point charge is placed at a distance away from the above frame () then:

image

  1. A
    charge oscillates along the -axis
  2. B
    it moves away from the frame
  3. C
    it moves slowly towards the frame and stays in the plane of the frame
  4. D
    it passes through the frame only once.

Solution & Step-by-step Explanation

The four positive charges exert an attractive force on the negative charge toward the center of the square frame. For a small displacement , the resultant force acts as a restoring force proportional to the displacement. When the charge reaches the center of the frame, the force is zero, but due to inertia, it moves to the other side, setting up simple harmonic oscillations along the -axis.

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Four point charges of same magnitude () are placed at four corners of a rigid square frame as shown in figure. The plane of the frame is perpendicular to -axis. If a point charge is placed at a distance away from the above frame () then:

image
A
charge oscillates along the -axis
B
it moves away from the frame
C
it moves slowly towards the frame and stays in the plane of the frame
D
it passes through the frame only once.

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