UNIT 5: WATER
Instructions
1. Cut the plastic bottle as shown in Figure 18.
Figure 18 - Cutting plastic bottle (To be done by teacher)
2. Keep lower part of the cut plastic bottle on the table.
3. Invert the upper part of the bottle and hold it.
4. Place a layer of big pebbles at the bottom of the bottle.
5. Place a layer of small pebbles on the big pebbles.
6. Now place the sand on the small pebbles. Tap the sand to make it tight.
7. After adding all three layers, this half bottle is kept over the rst half bottle that was
kept on the table.
A model lter bed
Filter the muddy water as follows:
(i) Pour the muddy river water into the model lter bed
(ii) Observe the water passing through the
dierent layers and falling into the container below.
Observe the water collected in the container.
(i) Is the water in the container of the same colour as the muddy water before?
...............................................................................................................................................................................................................................
plastic bottle
(inverted upper part)
sand
small pebbles
big pebbles
muddy water
sand
small pebbles
big pebbles
container
(lower part of plastic bottle)
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