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.
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!
Why is it impossible to pull two books apart?
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!
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. Use of ball bearings: Ball bearings are used to reduce friction.
What is sliding friction example?
Examples of Sliding Friction Rubbing both the hands together to create heat. A child sliding down through a slide in a park. A coaster sliding against a table. A washing machine pushed along with the floor.
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.
Why a moving ball get to rest after sometime?
Physical Science Ball comes at rest after sometime because if friction. That is , due to opposing force acting in the direction opposite to motion.
What’s another name for sliding friction?
Sliding friction (also called kinetic friction) is a contact force that resists the sliding motion of two objects or an object and a surface.
What are 5 examples of friction?
10 examples of friction in our daily life
- Driving of a a vehicle on a surface.
- Applying brakes to stop a moving vehicle.
- Skating.
- Walking on the road.
- Writing on notebook/ blackboard.
- Flying of aeroplanes.
- Drilling a nail into wall.
- Sliding on a garden slide.
Can you pull apart two interleaved phone books?
Try pulling apart two interleaved phone books and you’ll inevitably be defeated by huge frictional forces. Just how these forces arise has been a long-standing mystery… until now. A famous demonstration of the counterintuitive power of friction involves two telephone directories with their pages alternately interleaved.
Why does it take longer to pull apart two 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 do you split a book into two books?
Open both books and overlap their back covers at least halfway. One by one interleave the pages of the two books by folding down a page from the left book then a page from the right book on top of that, and then a page from the left book again. Continue alternating in this fashion for about a dozen pages. Now try to pull the books apart.
What is the force that pushes books together?
Of course, friction only occurs when two surfaces are pushed together, and experimenters often explain that gravity is the force that pushes the pages together in these experiments. That turns out to be easily refuted by turning the books on their side or holding them vertically.