When two displacements represented by y₁ = a sin$${\left( {\omega t} \right)}$$ and y₂ = b cos$${\left( {\omega t} \right)}$$ aresuperimposed the motion is

The oscillation of a body on a smooth horizontal surface is represented by the equation,
X = A cos$$\left( {\omega t} \right)$$
where X = displacement at time t
$$\omega $$ = frequency of oscillation
Which one of the following graphs shows correctly the variation a with t?
Here a = acceleration at time t
T = time period

A particle of mass m oscillates along x-axis according to equation x = asin$$\omega $$t. The nature of the graph between momentum and displacement of the particle is

Two particles are oscillating along two close parallel straight lines side by side, with the same frequency and amplitudes. They pass each other, moving in opposite directions when their displacement is half of the amplitude. The mean positions of the two particles lie on a straight line perpendicular to the paths of the two particles. The phase difference is