Why is the graph of the parametric equation like this

I am graphing r = [5cost, 5sint] from t = 1:3000. I was wondering why the graph shown is an annulus instead of a circle? I graphed the same for t = 1:0.1:300 and it shows a circle that is much thinner.

Any insights why this happens? They are both circular functions, supposedly without any thickness.

Answer 1

[KSSV]

t = linspace(0,2*pi,100) ;
r = [5*cos(t) ; 5*sin(t)]  ;

plot(r(1,:),r(2,:))