Why does one end of a fan look like part of a circle?

Question

When you make a paper fan the end where you fan the air to yourself looks like part of a circle. Why does it do that? My teacher says it's mathematically, but I need an explanation! I've been wonder this forever!!! Please help? I need help on a report! Or maybe so sources I can research at? Thank you!

Answer 1

All parts of the fan are of equal length, and equally distant from the part you hold.  All points on a circle are equally distant from center.

Answer 2

This is only optical and meteorological phenomena that cause a effect of light to appear in the circle when the Fan is running speedy.

B'coz fan is symitrical in shape & all its blade is equal in length & they are fitted to its rotor.

And we know that in circle all points on its circumferance has equal distance from its centre.

Thanx