Why does electricity only pass through one person when touched by another person near an electrical cable?

The reason why electricity passes through the human body involves the principles of electricity in physics. When the human body becomes part of the circuit, the current will pass through the human body, and the reason why the human body can become part of the circuit is because the human body has a certain conductivity. The following explains why current only passes through another person when that person touches near the cable:

The conditions under which the current flows

Current always tends to flow along a closed loop, that is, a complete circuit must be formed. The circuit usually consists of a power supply, a load (such as a light bulb, a motor, etc.), and a wire connecting the two. When the human body touches a part of the circuit, if a closed loop can be formed, the current will pass through the human body.

Human conductivity

The human body is not an ideal insulator, but has certain electrical conductivity. Skin is the outermost tissue of the human body, and its electrical conductivity is affected by a variety of factors, including the moisture of the skin, its thickness, and the presence or absence of wounds. Electrical conductivity increases when the skin is moist or sweaty.

Form a closed loop

• Single point contact: If a person only touches one end of the cable, and the other end of the cable does not form a closed loop (such as not being grounded or connected to the other pole of the power supply), then the current will not pass through the person.

• Two-point contact: When a person touches both ends of a cable at the same time (for example, touching the live wire with one hand and the ground wire with the other), or touching a charged point and another point capable of forming a closed loop (such as the ground), the current passes through the person to form a closed loop.

• Indirect contact: If one person touches a live cable and another person touches that person's body, then the second person also becomes part of the circuit, and the current passes through both people to form a closed loop.

Specific scenario analysis

Suppose there is a live cable, and when the first person touches the cable, if the other end of the cable does not form a closed loop, the current will not pass through that person. But if the second person also touches the first person at this time, then the current may form a closed loop through the bodies of both people, causing the current to pass through.

Safety tips

• Avoid contact with live equipment: Direct or indirect contact with live equipment or cables should be avoided under all circumstances to prevent electric shock.

• Use insulating tools and personal protective equipment: When handling electrical equipment, you should use insulating tools and wear personal protective equipment, such as insulating gloves and shoes.

• Emergency treatment: In case of electric shock, cut off the power immediately and seek professional rescue as soon as possible.

Sum up

The reason current passes through the body is that the body becomes part of the circuit and forms a closed loop. Only when the human body or the human body together with others form a closed circuit will the current pass through the human body. Therefore, when handling electrical equipment, special care is needed to avoid the occurrence of accidental electric shock.