Referring the graphs, which of the following is/are correc?

Options

A. (a) The particle has stable equilibrium at point 3 and b.
B. (b) The particle is in neutral equilibrium at point b and 2.
C. (c) No power is delivered by the force on the particle at point 1, 3, and b.
D. (d) The particle has least kinetic energy at position 1.

Answer

A, C, D

Explanation

Option (a) is correct because at 3, force is opposite to displacement. At (b), `u` is minimum.
Option (b) is incorrect at 2, there is net force and hence no equilibrium.
Option (c) is correct because at `1,3` and (b) force is zero.
At (b), `(du)/(dx)=-F=0`
Option (d) is correct. Positive work is done after position 1, hence KE will increase. So KE is least at 1.