A particle of mass '$$m$$' moves in one dimension under the action of a conservative force whose potential energy has the form of $$U(x)=-\frac{\alpha x}{x^2+\beta^2}$$ where $$\alpha$$ and $$\beta$$ are dimensional parameters. The angular frequency of the oscillation is proportional to

In a simple harmonic motion, let f be the acceleration and t be the time period. If x denotes the displacement, then |fT| vs. x graph will look like,

A particle is subjected to two simple harmonic motions in the same direction having equal amplitudes and equal frequency. If the resultant amplitude is equal to the amplitude of the individual motion, the phase difference ($$\delta$$) between the two motion is