Bottle siphon water play

What you need

• Two plastic bottles or jugs
• A length of clear tubing or a straw taped to another
• A washing up bowl
• Food colouring if you have it

How to do it

1. 1

   Fill one bottle with coloured water and stand it higher than the empty one.

2. 2

   Fill the tube with water, holding both ends closed with your thumbs.

3. 3

   Put one end in the full bottle and the other in the empty one, then let go.

4. 4

   Watch the water flow, then raise the empty bottle higher and see it stop.

5. 5

   Try a longer tube and a bigger height difference and time each one.

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