A NEW EXPERIENCE

Ritu and Sunaina studied in the same class. They played together and commuted on the same bus to and from school.

- Vandana Gupta

One day, their science teacher showed them an experiment. He heated water in a pot. Then, he tied a balloon to the mouth of a bottle and placed the bottle in the hot water. The balloon inflated.

The teacher said, "Hot air is lighter, so it rises upwards. With this technique, people enjoy air travel by tying a basket to a hot air balloon."

When Ritu and Sunaina went to play in the evening, they told their friends, Becky and Tara, about the experiment.

"Why don't we make a hot air balloon and go for a ride?" asked Tara.

"But can small balloons carry our weight and fly?" Ritu asked. "We can send our dolls for an air ride, if not ourselves," said Becky, who loved her dolls a lot.

"Yes, we can do that!" Sunaina also got excited.

"Well then, you all come to my house. We'll work on the experiment," said Ritu.

"I have a packet of balloons at home; I'll get them," said Sunaina.

"I'll bring a bottle to tie the balloon," said Sunaina.

"I have a small basket at home; I'll bring it," Tara said.

They ran to get their stuff and gathered at Ritu's house with the objects.

They heated water in a vessel, put the bottle in it, and tied a balloon to its mouth. As soon as the water heated up, the balloon began inflating, and they jumped for joy.

They tied the mouth of the balloon with a thread, tied it to the basket, and waited for the basket to fly, but it didn't!

"I think the balloon is too small. We must increase the number of balloons; otherwise, the basket won't fly," said Ritu.

They inflated many balloons and tied them to the basket, but the basket still didn't fly. They were disappointed.

Sunaina said, "Sir said that because hot air is light, it rises up. But our balloons have cooled down! How will the basket fly?"