Can you lift a car with two phone books?
Can you lift a car with two phone books?
Summary: Astonishingly, it turns out to be practically impossible to separate two interleaved phone books by pulling on their spines, however much force is applied. It is even possible to suspend a car from them.
What happens when you pull on the interlaced books?
It turns out that when you try to pull the two books apart, the interleaved pages in the middle get squished together harder—this increases the normal force between them, thereby increasing overall friction. This means that the harder you pull, the higher the friction, and the harder the pages are to pull apart!
How much force does it take to pull two phone books apart?
Still, they measured 8,000 lbs of force to pull those books apart. If you guess that each has about 400 pages (800 total), that’s around 10 lbs per page, which would be stretching it even if the pages were taped or glued together!
Can you lift a car with two phone books science buddies?
The pages of the sticky note pads are held together by friction. Even a small number of interleaved pages can result in a surprisingly large amount of friction, making the sticky notes impossible to pull apart. This phenomenon is commonly demonstrated with phone books.
Can you pull two phone books apart?
Friction. The force of friction acting on the pages is a major reason that pulling the books apart is so difficult. The fact that the pages of two phone books are interleaved means that friction as well as weight is preventing them from being separated.
Can we reduce friction?
Answer: Friction can be reduced to a great extent by polishing surfaces or by using a large amount of lubricants such as oil, water, or grease but we cannot reduce friction to zero.
Why is two interleaved books so hard to separate?
Does flipping a page shows friction?
Flipping a page: Friction allows us to flip the page from corners. Without friction, the pages will slip through our hands. It is an example of the application of rolling friction.
How do you do friction for a science project?
To test how much force is needed to overcome static friction, you can try dragging a shoe over various surfaces.
- Cut a rubber band in half.
- Tie one end to a shoe.
- Tug on the other end of the rubber band until the shoe starts moving.
- Measure how far the rubber band had to stretch in order for the shoe to move.
How do you separate two books?
60 second suggested clip1:052:41Inseparable Books Experiment – FRICTION – YouTubeYouTube
How friction is increased?
Friction can be increased by increasing the roughness of the surfaces in contact. For example, treading of shoes and tires is done to increase friction. When friction is undesirable we have to reduce the friction.
Why friction is a necessary evil?
Frictional force causes a lot of losses in general upkeep and wear and tear of machinery. But almost all crucial tasks cannot be carried out without the presence of friction. Basic activities like walking and writing on a surface are possible due to friction. Hence it is considered as a necessary evil.