The story of electricity (1): static electricity, conductor and insulator.

Since electricity was discovered and used by human beings, it has been closely related to people's daily life. It took only 400 years for human beings to truly understand the use of electricity, and only 200 years for the real large-scale use of electricity. The large-scale use of electricity has greatly saved human physical and mental labor, promoted the second industrial revolution and brought great impetus to human society.

This article will take you step by step to review the history and anecdotes of electricity, and the story will begin with the static electricity around us.

1703, after Newton became the president of the Royal Physical Society, he put his own people in a key position, and 35-year-old Francis Haux was responsible for demonstrating experiments.

Haux racked his brains every week to impress his boss with eye-catching experiments. He came up with this experiment, using a rotating glass ball, pumping the air out of the ball with a new machine and rotating the glass ball. When all the candles in the room went out, Hauksbee put his hand on the glass ball. There was a strange ethereal light in the glass ball, which began to form around his hand and kept beating. People present had never seen this kind of light, which was regarded as the masterpiece of God at that time.

Haux was never aware of the importance of his experiment. He lost interest in this wonderful luminous sphere and turned to other experiments to verify Newton's other theories. He never imagined that with the beginning of the Enlightenment in Europe, this experiment inadvertently opened an electrical revolution.

Ironically, Hauksbee's new machine was not accepted by most intellectuals, but attracted magicians and buskers who claimed to be electricians.

At a dinner party for the Earl of Austria, the electrician put some feathers on the table, wiped the glass rod with a silk handkerchief, and then lifted the feathers with the glass rod, which surprised the guests. Then he electrified himself with Hauksbee's equipment and lit it for the guests, probably to scream with excitement. Finally, this is his masterpiece. He put a glass of brandy in the middle of the table, electrified it again, and lit the brandy with the spark of his fingertips.

In fact, Hauksbee's experiment produced electrostatic charge, but as early as the early heyday of ancient Greece, this indistinguishable and fleeting mysterious electrostatic phenomenon had been recorded and became a special research object. In 600 BC, Thales, an outstanding philosopher and astronomer, observed a rare orange amber in the prosperous Ionian port of Miletus, which was as hard and transparent as a gem. Cyrus found that when he rubbed amber with a cloth quickly, it seemed to come alive, and at the same time, a slight object, such as feathers, straw or leaves, flew to it and stuck to it, then gently left and floated away.

Back in Haux's era, electrical fanaticism swept across Europe, and the performances became more and more grand. With the enlightenment of Europe, electricians began to think about deeper problems, not only how to make the performance more exciting, but also how to control this magical power. Some people even began to think about how to explain the phenomenon with reason, and what role this phenomenon has besides the magical spark of entertainment.

A bankrupt silk dyer in Carter workhouse in central London discovered the conductive characteristics of electricity and defined the concepts of insulator and conductor.

Stephen Gray was born in a handicraft family in Canterbury, England. After receiving some basic education, I followed my father as an apprentice in dyeing clothes, and later became a very successful silk dyer. He is very interested in natural science, and he is fascinated by the sparks generated by static electricity in silk at work.

Unfortunately, a serious accident ended his career, leaving him penniless and boarding in Carter workhouse in his later years. In the past 400 years, this workhouse has been accommodating young orphans and old people. 18 In the 1920s, it became Stephen Gray's home and started his new life.

In the quiet life of the workhouse, Gray has enough time to conduct his own electrical experiments.

On one occasion, he started his experimental performance under the gaze of a large audience. Stephen Gray built a big wooden frame and hung two swings on the top beam. The rope was made of silk. He also has a Hauksbee machine to generate static electricity. He let an orphan in the workhouse lie across two swings and put some gold foil in front of him. Then he turned the handle of Haux's machine and electrified the boy through the connecting rod. This experiment is called the "flying boy" experiment.

The boy's hand is close to the gold foil, and the gold foil jumps on the boy's finger and bounces off quickly. Some viewers even said that they saw small sparks flying between the boy and the gold foil. The performance was wonderful and successful.

But Gray is an exploratory person, and he is not addicted to the pleasure brought by appearances. He thinks it has other meaning. Electricity can move, from the motor to the boy's body and then to the boy's hand, but the silk rope stops it.

Mysterious currents can pass through some objects, but not others. So Gray divides matter into two categories. He called them insulators and conductors. Insulators, such as silk, hair, glass and resin, keep the charge in their bodies and prevent it from passing through. On the contrary, conductors allow current to flow, such as boys and metals.

He further experimented with other materials between the glass tube and the ivory ball, using metals such as iron, copper wire, copper coin, tin and silver; Yes, they carry current, not conductors. Then try non-metals, such as stones, and some vegetables, which are not conductive and are insulators.

This division is very important and continues to this day.

Later, Gray put copper wires of different lengths between glass and ivory balls to do experiments to verify how far the electric energy is conducted. He had only 800 feet of copper wire, and he could still see the phenomenon that electricity could be conducted. In this way, he discovered the phenomenon of electric energy conduction.

Gray devoted the rest of his life to the study of electricity.

In the 1930s, Gray's experiment shocked all the audience, but he had a frustrating shortcoming. Although Gray tried many times, he couldn't store the electricity he generated for a long time. The electricity passed from the motor to the boy and disappeared soon after. How do people find out how to store electric energy? It happened not in Britain, but in the European continent across the Taiwan Province Strait.

to be continued ...

Welcome everyone to pay attention to the official account of "Ten Dimensional Physics" WeChat.