How can I make my pointed pencil self-reliant well?

ByDavid

During boring classes, you may strike a pinch at the tip of your hands or fingers and take a balance to balance. The most difficult thing is a pointed pencil with a small contact area. How many independent physics-related movies are released on YouTube to see how well they can be self-reliantMinutePhysicsThe channel is thinking.

How Long Can You Balance a Pencil? - YouTube


How many seconds can you balance your sharp pencil on your index finger. Everyone challenged when they were children, the one who was able to balance the longest was supposed to be a hero of my friend.


If you have a soft fingertip, you can take a few seconds to balance, but it is very difficult to stand on a desk. It seems to be self-sustaining if the gravity directly under the center of gravity of the pencil and the repulsive force from the contact point of the desk and the pencil are balanced ... ....


Actually pencilVerticalIt is impossible to stand on the balance of the force, the pencil will collapse without stopping for a moment.


Since gravity and repulsion should theoretically be balanced, should be balanced carefully should be self-sustaining. HoweverNanounit·PicoEven with the unit gap, the pencil collapses. In the calculation of Minute Physics, "one ten-thousandth of an atom", that is, 0.01 picometer (10Femto meter) Is also out of position.


Nonetheless, there seems to be something in the world that has a surprisingly delicate balance. For example, a circus acrobat ... ...


A drones that throws a thin rod and catches it, taking balance as it is.


Whether it is a story of 0.01 picometer unit, such as a combination of rocks that once collapsed, it seems that it will not be possible to return again.


Minute Physics explains that these circumstances and the fact that pencils are placed on a desk are different. In the case of acrogators and drones, it is possible to actively "keep balancing". In the case of rocks, unlike sharp pencils, it is not a single point of grounding, so it is well balanced.


Then, what is necessary to make the pencil self-sustaining with just one point?


Even if it is standing perfect vertically even with a displacement of 0.01 picometer, the atmosphere will interfere with us. It is natural that the vehicle collapses if the wind blows, but otherwise the air is constantly vibrating and it is no doubt that it will cause a displacement in picometer units. Therefore, "To be a vacuum" is a prerequisite if you want to make a sharp pencil autonomous.


Also, in order to prevent deviation due to micro-shaking of molecules of the pencil itself, it is necessary to cool down the quinch to suppress the activity of the molecule to the utmost limit.


In addition, when all the various uncertainties are cleared, the pencil will become self-sustaining. In other words ...


In a vacuum, with pencils sufficiently cooled, you can finally stand still by standing the pencil vertically and balancing ... ... that being self-sustaining a pointed point pencil is "physically impossible" It can be said.


"Impossible!"


Nonetheless, you should be able to keep pencils upright so that acrobats can stand on the sticks if you actively balance. By the way, when MinutePhysics challenged with fingertips, the record was 1.3 seconds ... ....