2. We can see that water has a force when it is rushing over a waterfall or down a stream.

3. Water also uses a force that keeps things afloat. This force is called…… We can test this!

4. To test for upthrust we need…… …a container of water and…… …a balloon.

5. The balloon will float on the surface of the water.

6. You can feel an invisible force pushing the balloon back up. If you try to push the balloon down it will not move

7. This invisible force is called upthrust. You push down… …the upthrust pushes the balloon back up.

8. It is upthrust that helps some things to float on water.

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