Physics-
General
Easy
Question
Four point +ve charges of same magnitude (Q) are placed at four corners of a rigid square frame as shown in figure. The plane of the frame is perpendicular to Z ̶axis. If a –ve point charge is placed at a distance z away from the above frame (z<<L) then
- – ve charge oscillates along the
axis.
- It moves away from the frame
- It moves slowly towards the frame and stays in the plane of the frame
- It passes through the frame only once.
axis.
The correct answer is: – ve charge oscillates along the axis.
The negative charge oscillates, the resultant force acts as a restoring force and proportional to displacement. When it reaches the plane 
, the resultant force is zero and the mass moves down due to inertia. Thus oscillation is set.
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