Collection Screen Savers Win Wallpaper Mac Wallpaper Movie Gallery Resistance Resistance refers to the property of a substance that impedes the flow of electric current.
Some substances resist current flow more than others.
If a substance offers very high resistance to current flow it is called an insulator. If its resistance to current flow is very low, it is called a conductor. Resistivity refers to the ability of substances to resist current flow. Good conductors have low resistivity and insulators have high resistivity. Resistance at the Molecular Level Resistance to current flow occurs at the molecular level of substances.