Final answer:
Materials such as glass, rubber, and paper that do not allow electrical current to flow through them are called 1. insulators. These materials prevent charge movement since their electrons are tightly bound to atoms.
Step-by-step explanation:
Material such as glass, rubber, or paper around a conductor that does not allow current to pass through it is called an insulator. These materials are essential in preventing the unintended flow of electricity, ensuring safety and functionality in various electrical applications. Unlike conductors, which have loosely bound outer electrons that allow for easy movement of charge, insulators have their electrons tightly bound to atoms, preventing the free flow of charge. In an insulator, charge flows only with great difficulty, or not at all.
Examples of insulating materials include plastics, glass, ceramics, and wood. The resistivity of insulators is far greater than those of conductors, making them ideal for safeguarding against electrical transmission.