How to Throw

• Something to launch your projectile. If you have an EMP launcher and can use it safely then use that, otherwise you can try a catapult, or even a pea shooter (which will be difficult - it is important to have a consistent launch speed).
• A projectile - a lighter one is safer, but it needs to be heavy enough that it won't be affected by air resistance too much.
• A long measuring tape.
• Someone to launch and someone to observe and measure the distance.
• A large protractor to measure angles.

1. You can do this outside if it is a very still day - but if it is windy (particularly if your projectile is light) you will need to stay inside.
2. Carry out one or two practice launches to see how far your projectile goes. Hold the launcher in the same position and at the same angle and check that you can fire it consistently so that it reaches the same distance.
3. Put the tape measure along the ground from your launch position to beyond where you hope the projectile will land.
4. Now angle your launcher using the protractor at 20, 30, 40, 45, 50, 60 and 70 degrees to the horizontal and fire your projectiles again. Fire five times at each angle and note the distance the projectile has reached each time.
5. Find the average distance travelled at each angle by adding the five distances up and dividing by five and make a note next to the angle.
6. Which angle produced the greatest travel distance?

The EMP launcher works well because at a fixed voltage it launches the disk at exactly the same speed. To achieve the same result you will need to either carefully construct a catapult which can drawn back by the same amount each time, or use the same amount of puff with your pea shooter (something that is tricky to do).

If your launcher is good you should find that the projectile flies the furthest at 45 degrees. There is a balanced reached between the amount of time the projectile stays in the air and distance it travels during this time.

When launched at a low angle to the ground the projectile travels quickly along the ground but doesn't spend much time in the air - the result is the projectile hits the ground before it has travelled very far.

When fired at a large angle to the ground the projectiles spends a lot of time in the air but doesn't cover much ground in this time.

The optimal distance for launching the projectile is 45 degrees where the projectile spends just the right amount of time in the air to cover the greatest distance.

Do not use a heavy projectile - be careful of people's heads, making sure they stand back when the projectile is in flight.