Discovery Primary Science Activities- 3

Experiment 3: Design a Boat

This week we are learning about floating and sinking

Equipment:

• Plasticine
• Container filled with water
• Peas

Skills: Investigating and experimenting, designing and making

Experiment:

Note: For fair testing give each group the same amount of Plasticine.

1. Make predictions.
2. Roll the Plasticine into a ball and put it into the water. What happens? (It sinks).
3. Now see if they can get it to float (You do this by making the boat hollow on the inside)
4. Once they have it floating can they get it to take some ‘passengers’ (dried peas)?
5. Can they alter the shape so that the boat will take more ‘passengers’ before it sinks?

Results:

The ball of plasticine sinks to the bottom. When we made the plasticine into boats (changed the shape and made the inside hollow), the boat floated. We then added passangers, when we put in too many passangers the boats sank)

Background information: Water pushes upwards with a force called ‘upthrust’. (You can feel this if you try topush a light object such as a balloon or aeroboard under water). The shape of a ‘boat’affects the weight (passengers/cargo) it can hold. The more water that the boat displaces the more it will float and therefore the more weight it can take.