A particle of mass m moves in a straight line. If v is the velocity at a distance x from a fixed point on the line and ${\mathrm{v}}^2=\mathrm{a}-{\mathrm{bx}}^2$, where a and b are constant, then

the motion continues along the positive x-direction only

the particle oscillates with a frequency equal to $\frac{\sqrt{\mathrm{b}}}{2\mathrm{\pi }}$

the motion is simple harmonic

the total energy of the particle is ma