Western Treatment Plant Explorer : Teacher Resources : Resource 12
Resource 12
Siphoning ¹
From the shape of the toilet bowl you will notice that the water must first flow uphill before running down the waste pipe. This uphill flow of water is made possible by the siphon effect. In this activity you are going to investigate how siphons work.
You will need:
- a clean plastic container
- a bucket
- food dye
- clear plastic tubing.
Steps
Do this in the 'wet' area of the science lab.
- Fill the plastic container with water, add a few drops of food dye and give it a stir. The food dye is just to enable you to see what happens.
- Put the container of water on a bench or stool and the bucket on the floor.
- Put one end of the tubing in the plastic container and the other end over the empty bucket. (The end of tubing over the bucket must be below the level of the plastic container.) Now suck the lower end of the tubing until the water flows around the bend.
- Try this again, but with the plastic container and the bucket on the same level.
- Now try it with the bucket on the bench and the plastic container on the floor.
- Can you explain what is happening in each case?
Showing the siphoning effect.
¹ Based on an activity from: Keith McTaggart and Paul Saddler 1993, Flushing Dunnies, Melbourne Water and Science Teachers Association of Victoria.