What Affects the Flow of Electricity?
Electricity flows more easily through certain materials than others. Substances such as metals and the earth, which offer very little resistance to the flow of electric current, are known as 'conductors.'
Glass, plastic, porcelain, clay, pottery, dry wood, and similar substances, which prevent the flow of electricity, are known as 'insulators.' However, air, which is usually an insulator, can become a conductor under certain conditions, leading to electrical arcs or lightning.
How Does Water Affect the Flow of Electricity?
Pure water is a poor conductor of electricity. However, when water contains small amounts of impurities such as salt, acid, solvents, or other materials, it can become a conductor or even a better conductor. This principle also applies to substances that typically act as insulators. For instance:
- Dry wood typically acts as an insulator, slowing or stopping the flow of electricity. However, when it is saturated with water, wood becomes a conductor.
- Dry skin has a fairly high resistance to electric current. But when skin is moist or wet, it becomes a conductor.
This means that anyone working with electricity in a damp or wet environment needs to exercise extra caution to prevent electrical hazards.
What Causes Shocks
Electricity travels in closed circuits, normally through a conductor. However, there are instances when a person's body, which is an efficient conductor of electricity, inadvertently becomes part of the electrical circuit. This scenario can result in an electrical shock. Shocks occur when a person's body completes the current path with:
- both wires of an electric circuit
- one wire of an energized circuit and the ground
- a metal part that accidentally becomes energized due, for example, to a break in its insulation
- another "conductor" that is carrying a current
Effects On The Body
The severity of a shock depends on:
- the amount of current flowing through the body
- the current's path through the body
- the length of time the body remains in the circuit
- the current's frequency
A severe shock can cause considerably more damage than meets the eye. A victim may suffer internal hemorrhaging, as well as the destruction of tissues, nerves, and muscles, which may not be readily visible. Additionally, it can cause renal (kidney) damage. It is crucial that if you or a coworker receives a shock, you seek emergency medical help immediately.
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1-4. What is the result when a person's body becomes part of an electrical circuit?
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