NCERT Book Class 5 EVS Experiments with Water

7. Experiments with Water

What floats – what sinks?

Ayesha was waiting for dinner. Today Ammi was making her favourite food – puri and spicy potatoes. Ayesha watched as her mother rolled out the puri and put it in the hot oil. She saw that at first the puri sank to the bottom of the pan. As it puffed up, the puri came up and started floating on the oil.

One puri did not puff up and did not float like the others. On seeing this, Ayesha took some dough and rolled it into a ball. She flattened it and put it in a bowl of water. Alas! it sank to the bottom and stayed there.

Think what would happen if

• Ayesha put a puffed puri in a bowl of water. Would it sink or float?
• You put a steel plate on water. Would it sink or float? What would happen to a spoon?
• Would the cap of a plastic bottle sink or float on water?

In the evening Ayesha went for a bath. She had just come out when her mother called, “Ayesha, you have dropped the soap in the water again. Take it out and put it in the soap case.” Ayesha was in a hurry and the soap case fell out of her hands. It started floating on water. Ayesha gently put the soap in the soap case. She saw that the case continued to float, even with the soap in it.

Have you seen that some thing float on water while others sink? Think how this happens! The poem here raises such questions.

Do this and find out

• Do this experiment in groups of four friends. Each group will need a big pot filled with water and the things listed in the table. Put each thing one-by-one in water and observe.

Please refer to attached file for NCERT Class 5 EVS Experiments with Water