What Is an Electric Current?

Scientifically, the amount of electricity passing through any cross section of a conductor in unit time is called the current intensity, referred to as the current, the current symbol is I, and the unit is ampere ( A ), referred to as "An" (André Mary Amper, 1775-1836 In 1986, French physicists and chemists made outstanding achievements in the study of electromagnetic effects and also contributed to mathematics and physics. The international unit of electric current is named after his surname). ^[1]

Thermal effect

When a conductor is energized, it generates heat. This phenomenon is called

Current is divided into

The main factors that cause electric shock casualties are generally the following:

1. The amount of current flowing through the body. According to the analysis of the electric shock accident, when the power frequency current is 0.5 to 1 mA, people feel numbness or pain in their fingers, wrists; when the current is increased to 8 to 10 mA, the acupuncture sensation and pain increase, spasm occurs, and they are charged. Body, but can finally get rid of the charged body; when the contact current reaches 20 to 30mA, it will quickly paralyze the person. Cannot get rid of the charged body, and the blood pressure will rise, and breathing will be difficult; when the current is 50mA, the person will be paralyzed and the heart will start It trembles and can be fatal after a few seconds. The greater the current through the human body, the stronger the physiological response of the human body, the more serious the pathological state, and the shorter the lethal time. ^[18]

2. The length of the power-on time. The longer the current passes through the body, the more serious the consequences. This is because the longer the time, the lower the resistance of the human body and the higher the current. At the same time, every time the human heart contracts and dilates, there is a time interval of 0.1s in the middle. During this interval, the human body is most sensitive to the effects of current. Therefore, the longer the electric shock time, the greater the number of coincidences with this gap period, and the greater the danger caused. ^[18]

3 The path of electricity through the human body. When current passes through important internal organs of the human body, the consequences are severe. For example, through the head, the nerves of the brain are destroyed and people die. Passing the spinal cord can damage the central nerve and paralyze a person. Passing through the lungs makes it difficult to breathe. Passing the heart can cause the heart to tremble or stop beating and die. Of these types of injuries, heart injury is the most serious. According to accident statistics, the most dangerous way through the human body is from hands to feet, followed by hands to hands, and the least dangerous is from feet to feet, but it may cause secondary accidents. ^[18]

4 Kind of current. Current can be divided into direct current and alternating current. Alternating current can be divided into power frequency power and high frequency power. These currents are harmful to the human body, but to different degrees. The human body's ability to endure direct current and high frequency power is stronger than power frequency power. Therefore, power frequency electricity is the most harmful to the human body. ^[18]

5. Health status of electric shockers. The consequences of an electric shock are related to the health of the person who is receiving the shock. According to statistics, muscular people and adults have a stronger ability to get rid of electric current than children, and men have a stronger ability to get rid of electric current than women. Electric shock is most dangerous for patients with heart disease, lung disease, endocrine disorders, and mental illness. They have the highest death rates from electrocution. In addition, those who are psychologically prepared for electric shock will be harmed lightly. ^[18]