How Do I Convert Circular Parametric Equations Using Arc Length as a Parameter?

[waealu]

For an assignment, I am supposed to find the parametric equation for the circle:
x^2+y^2=a^2,
using as a parameter the arc length, s, measured counterclockwise from the point (a,0) to the point (x,y).

I understand that the parametric equation for a circle is x=a*cos(t) and y=a*sin(t), but I'm not sure what they are asking me to do in this problem.

Would anyone be able to get me started on this problem?

Thanks

 

[SammyS]

How is t (in radians?) related to the arc length, s?

 

[waealu]

Nevermind, I was able to figure it out. They are looking for x=a*cos(\Theta)=a*cos(s/a) and y=a*sin(\Theta)=a*sin(s/a).

Thanks, though.

 

[SammyS]

Yes.

You're welcome.