A postcard is tied on a rope. Effective trick and its solution

EFFECTIVE FOCUSES AND THEIR CLUES
Free library / Directory / Spectacular tricks and their clues

A postcard is tied on a rope. Focus Secret

Spectacular tricks and their clues

Directory / Spectacular tricks and their clues

Focus Description:

Put some postcards in the box. Take the rope, the end of which is also lowered into the box. Then lift it up high. At the end of the rope tied a knot with a postcard!

Focus secret:

You need two small magnets. One is glued from the inside to the end of the braid of the rope. There is also a small piece of the same rope. A postcard is tied to it with a loose knot. Another magnet is glued to the other end of this secret piece of string. A secret rope with a knot and a postcard is hidden in the box in advance.

It is worth lowering other postcards there and putting the rope end into the box, as the magnets will connect. It turns out that one of the postcards itself tied in a knot, which the audience will see.

Author: V.Postolaty

We recommend interesting articles Section Spectacular tricks and their clues:

▪ Guessing a word from a book

▪ Two jumping rubber bands

▪ intergrown paper

See other articles Section Spectacular tricks and their clues.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

Artificial leather for touch emulation 15.04.2024

In a modern technology world where distance is becoming increasingly commonplace, maintaining connection and a sense of closeness is important. Recent developments in artificial skin by German scientists from Saarland University represent a new era in virtual interactions. German researchers from Saarland University have developed ultra-thin films that can transmit the sensation of touch over a distance. This cutting-edge technology provides new opportunities for virtual communication, especially for those who find themselves far from their loved ones. The ultra-thin films developed by the researchers, just 50 micrometers thick, can be integrated into textiles and worn like a second skin. These films act as sensors that recognize tactile signals from mom or dad, and as actuators that transmit these movements to the baby. Parents' touch to the fabric activates sensors that react to pressure and deform the ultra-thin film. This ... >>

Petgugu Global cat litter 15.04.2024

Taking care of pets can often be a challenge, especially when it comes to keeping your home clean. A new interesting solution from the Petgugu Global startup has been presented, which will make life easier for cat owners and help them keep their home perfectly clean and tidy. Startup Petgugu Global has unveiled a unique cat toilet that can automatically flush feces, keeping your home clean and fresh. This innovative device is equipped with various smart sensors that monitor your pet's toilet activity and activate to automatically clean after use. The device connects to the sewer system and ensures efficient waste removal without the need for intervention from the owner. Additionally, the toilet has a large flushable storage capacity, making it ideal for multi-cat households. The Petgugu cat litter bowl is designed for use with water-soluble litters and offers a range of additional ... >>

The attractiveness of caring men 14.04.2024

The stereotype that women prefer "bad boys" has long been widespread. However, recent research conducted by British scientists from Monash University offers a new perspective on this issue. They looked at how women responded to men's emotional responsibility and willingness to help others. The study's findings could change our understanding of what makes men attractive to women. A study conducted by scientists from Monash University leads to new findings about men's attractiveness to women. In the experiment, women were shown photographs of men with brief stories about their behavior in various situations, including their reaction to an encounter with a homeless person. Some of the men ignored the homeless man, while others helped him, such as buying him food. A study found that men who showed empathy and kindness were more attractive to women compared to men who showed empathy and kindness. ... >>

Random news from the Archive

Magnetic cooling system based on shape memory alloys 07.10.2018

Modern refrigerators are quite different from their predecessors in their shape, the presence of touch screens and a richer set of functions. But inside the most modern refrigerators are all the same heat exchangers, piping, refrigerants and compressors, the operation of which provides a rather sensitive share in the total bills for the electricity used. Magnetic cooling technologies are considered one of the promising directions for the further development of refrigeration technologies, and recently a group of European researchers, having created an experimental magnetic system, showed that special alloys with the so-called shape memory can become a solution to most of the known problems.

Magnetic cooling systems work due to the magnetocaloric effect, which means that certain materials change their temperature when a magnetic field is applied to them. This technology, although it is considered a very promising direction, is still far from practical use due to the complexity of its implementation. Magnetic cooling systems often require magnets with superconducting windings, which themselves require expensive ultra-low temperature cooling.

To solve the above problems, researchers from the Technical University of Darmstadt and the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Germany, used a unique combination of magnets and special alloys. The magnets used were made from an alloy of iron, boron, and neodymium, while the shape memory alloys consisted of nickel, manganese, and indium.

The resulting magnets are the strongest permanent magnets in the world, capable of producing a magnetic field 40 times stronger than the Earth's magnetic field. And the special aforementioned alloy, meanwhile, provides the maximum temperature drop under the influence of a magnetic field. In addition, the alloy can return to its original shape after being deformed.

The operation cycle of the magnetic cooling system is rather complicated and consists of six steps. In the first step, which lasts only one millisecond, the alloy is exposed to a magnetic field and cools down. Then the influence of the magnetic field is removed and the alloy gives off its cold through the heat sink. The alloy heats up, but remains, at the same time, in a magnetized state. After that, the alloy is compressed by a special roller, which heats it even more, causes the internal structure of the material to change, which loses residual magnetization. After that, the alloy restores its original shape and becomes ready to repeat the cycle.

The prototype of the new magnetic cooling system is just a demonstration of how the use of shape memory alloys can reduce the number of permanent magnets required, the most expensive part of the technology. But by 2022, German scientists are already planning to build a larger-scale magnetic refrigeration unit of a new type, which will allow them to measure the parameters of its operation, including the depth of cooling, plus evaluate the energy and economic parameters of its operation.

Other interesting news:

▪ Magnetic filling in an empty sandwich

▪ 160A MOSFET for automotive applications from Toshiba

▪ 4D drone camera

▪ Supercapacitor made of cement and soot

▪ Fire-fighting eco-gel

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ section of the site Medicine. Selection of articles

▪ article Electrodynamics. History and essence of scientific discovery

▪ article In which state is mail addressed not by streets and house numbers, but by their descriptions? Detailed answer

▪ article Draftsman-designer. Job description

▪ article Control of a chandelier with four lamps. Encyclopedia of radio electronics and electrical engineering

▪ article Increasing the output power of the car radio. Encyclopedia of radio electronics and electrical engineering

Leave your comment on this article:

All languages of this page

Home page | Library | Articles | Website map | Site Reviews