Final answer:
An insulator is a material that resists the flow of electricity, with electrons tightly bound to atoms, making it difficult for charge to pass through. Plastics, glass, and wood are examples of good insulators widely used to ensure electrical safety.
Step-by-step explanation:
An insulator is a material that does not allow the transfer of electricity or energy due to the absence of free charge carriers such as electrons. In contrast to conductors like metals, where outer electrons are loosely bound and can move relatively easily, insulating materials have their electrons tightly bound to atoms, making it difficult for an electrical charge to flow through.
Common insulating materials include items like plastic, glass, and wood, which are integral in electrical applications to prevent unwanted flow of current and maintain safety.
Every material has its own capability to conduct or resist the flow of electrical charge. For instance, rubber is considered a good insulator, which means it does a great job of preventing the flow of electrical charge. On the other hand, materials such as pure water and dry table salt are also insulators, despite being quite different in nature from rubber or plastic.
A material's insulating properties are not just relevant to electricity; they can also apply to thermal energy, which is why some insulators are good for preserving heat. Ultimately, insulators play a crucial role in a wide variety of applications, from everyday electrical safety to advanced electronic components.