Science 3rd grade | UNIT 6: Forces and movement 6.2 Changing shape
Forces can change the shape of things.
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Activity 6.2a (Investigating forces)
You will need: a ball of clay - ruler
Drop a ball of clay from a height of 5cm. Observe what happens to the ball of clay. Write down your observations or draw what the clay looks like.
Shape the clay into a ball again. Drop the ball from a height of 10cm. What is the effect on the ball of clay?
Drop the ball of clay from three more different heights.
Use ideas about forces to explain the pattern.
Activity 6.2b (Dropping - a ball onto objects)
You will need: a small, heavy ball - different objects
Try using your hands to change the shape of the objects in front of you. Which were easy to change?
Use a wide, tall paper tube to drop a heavy ball onto the objects.
First, predict what will happen to each material. Use a table like this.
| Result | Prediction | Object |
| broke into 5 pieces | break | biscuit |
| clay | ||
| raw vegetable | ||
| cooked vegetable | ||
| stone |
Plan and carry out this test. How will you make it a fair test?
Record the results.
Questions
1) Do all materials change shape when they are pulled or pushed by hand?
2) List some workers who have to change the shape of materials.