Transcript: Ultimate disc

You know, not all summer sports have to conform to intense training regimes, personal bests, or even heavy competition. It can be as simple as throwing a frisbee round at the beach. But even the age-old art of throwing a flying disc has been transformed into the ultimate summer sport!

Hi, Sebastian Barr here – Ultimate frisbee player and student of physics at Monash University . But you don't need a science degree to guess that a sport called Ultimate has a lot going for it.

So let's check it out, starting out with the all-important frisbee, or disc, as we call it.

It has a standard frisbee shape, weighs 175 grams, and comes with tiny ridges on its surface which help provide grip and assist its flight through the air.

This calls for a quick lesson on frisbee throwing.

There are two main types of throw: the forehand, and the backhand. And the way the disc behaves in either one depends a lot on the grip you use.

Remember, whatever throw or grip you use, it's important to get the angle of release and the point of release just right … because, as you can see, pointing the disc too low or too high, or letting it go too early or late, doesn't give great results.

When done correctly, the throw provides the disc with a lot of forward momentum and angular momentum, or spin. These forces, along with lift, are all it needs to fly.

A disc with forward momentum splits the air at its leading edge as it flies, forcing some air over it and some under it. And the air that's deflected downwards provides an upwards push on the disc, giving it aerodynamic lift.

Lift is also provided to a flying disc by the Bernoulli effect. The Bernoulli effect results when air rushing over the top of the disc follows its slight inwards bend, and creates an area of low pressure which acts to suck the disc upwards.

So, spin – how does that come into play?

Spin is critical for a smoothly flying disc, as it provides stability and helps the disc to keep travelling in the direction it's already going. And the fact that the disc is thicker at its edges increases its angular momentum, or tendency to keep spinning.

And now back to our disc's little ridges. These create tiny areas of turbulence above the disc, which – strangely enough – help keep it attached to the airstream going over the top of it, allowing it to fly further.

But enough of the finer details of frisbee flight. Let's look at how the game is played.

You need a field that's 100 by 37 metres, with marked end zones, and two teams, each with seven players. The aim of the game is for you or your team mates to catch the disc while in your end zone as many times as possible.

And, unlike most other sports, there are no referees in Ultimate frisbee. Yes, players are responsible for calling their own fouls!

And once you play the game, you realise it wasn't called Ultimate by accident!