text: Parabolae show up everywhere in the world around us. For example:\n\n1. The reflecting mirror at the back of a headlight is a parabola. \n\n2. Parabolae are used to describe the trajectories of projectiles. \n\n3. Satellite dishes are parabolae. \n\n4. The surface of a fluid that is being rotated is a parabola. \n\n5. The microphones used to pick up distant sounds, like those on a football field, have a parabolic reflector behind them. \n\n6. The equation for the stopping distance of a car as a function of speed is a parabola. \n\n7. While the shape of a hanging cable between two poles is a catenary, but the shape of the cable holding up a suspension bridge is actually a parabola. \n\n8. The velocity as a function of radius in a pipe is a parabola. \n\n9. Under some conditions, orbits of meteors, comets, etc are parabolae.\n\n10. radio telescopes are shaped like parabolae\n\nand many others.