Science - Interesting Experiments

Grow a Garden of Mold 
Take a wide plastic jar, or a wide glass jar or a rectangle or a square, or even a round container. Put some bread pieces, vegetables pieces. meat pieces, wood, metal, rope, paper, plastic, cloth etc in it. Pour some water on it and cover the container with a plastic bag or sheet so that its humidity should not go out.

After a few days you will see several kinds of mold on different kinds of materials. You may keep it for one year, then see it how different it looks and how it smells. In fact it is the humidity in the environment which is the main cause of this mold. That is why in those regions where there rains a lot, most things, even shoes, get mold on them. Not to get mold on them, you must keep them in sunshine for sometime at time to time so that they are dry.

Why the Warm air of Earth Becomes Cooler on Mountains?
When hot air rises upward, then why the air on mountains is cool? Because the air becomes warm when it comes into contact with warm earth. So when the air comes into contact with warm earth and becomes warm, it starts rising. As it rises, it spreads in a wider area,  because air has lower pressure at higher altitudes. And because of spreading it becomes cooler.

Can you make your room cooler by leaving the door of your refrigerator open?
No, because refrigerator throws its own warm air outside, so the temperature of the room will not be affected by leaving the door of the refrigerator open.

Two Balloons: One Floats, Another Immerses
There are two balloons full of water. You want to make one balloon immersed in a hot water tub,  while the other one floating on the same water? What will you do? Fill one balloon with warm water, and the other one with cold water. The cold water balloon will immerse in the water, while the hot water balloon will float on the water. But for how long the cold water balloon will be immersed in hot water? Until its water becomes warm, so that it becomes lighter enough to float on the water. Later the cold water balloon will also come up.

Throw Your Golf Ball Farther Than Usual
If you want to throw your golf ball much far than usual, then play golf in mountains. Why? Because there the air is lighter, so it will go farther than it goes in flat plains.