Force of Friction: Paper Power

This simple experiment will show the power of frictional force when several sheets of paper are overlapped.

Materials needed.

2 notes or exercise books with approximately the same number of pages.

Procedure

On a table or flat surface, open the 2 books to their last pages and overlap their back covers.

Then take the next pages and overlap each one. Continue doing this until you reach their front covers.

Tell a friend to hold the binding of one book, and you hold the other one.

Try to pull the notebooks apart this way and see what happens.

The books should be very difficult to pull apart.

Explanation

The surface of paper appears smooth to the naked eye. But when viewed under a microscope it has a rough surface. When 2 or more paper surfaces come in contact, the surfaces interlock due to frictional forces. The frictional forces existing between the paper surfaces makes it difficult to pull the notebooks apart.

Science Experiments you can do at home ( CAN COLLAPSE)

This experiment will show how you can cause an aluminum can to implode.

Materials needed

• tablespoon ? of water.
• Empty aluminum soft drink can.
• Hot plate (or electric stove burner).
• Bowl filled with ice water.
• Tongs  enough to fit around a can.

Steps

1.Put the water in the empty aluminum can.

2. Heat the can on a hot plate until the water is boiling and steam is escaping from the opening.

3.Place a bowl of ice water next to the hot plate.

4. Carefully  use tongs to grab the can. Carefully and quickly flip the can upside down into the bowl of ice water.

The can should implode

Implode a soft drink aluminum can. Explanation

The steam coming from the can is the water vapor escaping as the water is boiling. Not only does the water vapor escape out of the can, it also pushes out any air that was in there before you heated it. When the can is flipped over into the ice water bath, the remaining water vapor cools, condensing back into liquid water. The amount of water vapor left in the can is equal to about one drop of water. Since all the air was pushed out earlier and now there is only one drop of water left in the can, the air pressure on the outside of the can pushes in on it, causing a sudden collapse, or implosion.