The position vector of a particle is r→ = (a cos ωt)î

The position vector of a particle is r^{^→} = (a cos ωt)î + (a sin ωt)ĵ , The velocity of the particle is

1. directed towards the origin
2. directed away from the origin
3. parallel to the position vector
4. perpendicular to the position vector

r^{^→} = (a cos ωt)î + (a sin ωt)ĵ

v^{^→} =	dr^{^→}	=	d	{ (a cos ωt)î + (a sin ωt)ĵ }
	dt		dt

= (-aω sin ωt)î + (aω cos ωt)ĵ
= ω [ (-a sin ωt)î + (a cos ωt)ĵ ]

Slope of position vector =	a sin ωt	= tan ωt
	a cos ωt

& slope of velocity vector =	-a cos ωt	=	-1
	a sin ωt		tan ωt

∴ velocity is perpendicular to the displacement.