What material is typically used for cable insulation?

Cable insulation is commonly made from rubber due to its excellent electrical insulating properties and flexibility. Rubber has a high dielectric strength, which means it can withstand high voltages without allowing electric current to pass through, making it an ideal material to prevent short circuits and electrical shocks. Its ability to withstand environmental factors such as moisture and temperature changes further enhances its suitability for outdoor applications and varying conditions.

In contrast, metal is a conductor of electricity and would not serve the purpose of insulation. Wood, while it can sometimes be used in specific applications due to its natural insulating properties, lacks the durability and consistent performance of rubber. Glass, although it can act as an insulator, is less practical for cable insulation because of its brittleness and susceptibility to breakage under stress, making rubber the preferred choice for most electrical cables.