# Conics

## Parabola

Binoculars have concave and convex lens inside them. The concave lens' help transfer the light accurately as the light goes through the convex lens at the end of the binoculars.

The new Margaret Hunt Hill Bridge is a parabola. The 58 cables all align on the focus of the the parabola for top strength.

## Hyperbolas

The hyperbolas of the stitching on the baseball create wind resistance. This allows pitchers to be able to throw different spins on the ball. They are also for grip.
The light that leaves the top (and bottom) can be thought of as a cone with vertex in the center of the light bulb, and the wall acts as a vertical cross section

## Ellipses

Tennis rackets have elliptical cross sections to provide a more rigid percussion region and causing better control over tennis balls.
The ellipse occurs because of the angle of the light hitting the surface.

## Circle

It is a circle so that every player is at least 10 yards from the ball. The radius is the same distance all around.
It has to spin to create the pressure differentiation between the upper and lower surfaces in order to fly. The circular frame is more aerodynamic which allows is to rotate faster.