Force acting on a particle moving along x-axis as shown in figure. Find points of stable and unstable equlibrium.
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Answer

A, B, C, D

Explanation

At `A,x=0` and `F=0`
For `xgt0, F= + ve` i.e. force is in the direction of displacement. Hence A is unstable equilibrium position.
same concept can be applied with E also.
At point `C,F =0`
for`xgtx_C , F = -ve`
Displacement is positive and force is negative (in oppsite direction of displacement). therefore, C point is stable equilibrium point.