In science, resistance refers to the ability of a material to resist the flow of electrical current. It is measured in units called ohms and is represented by the symbol "R".
Resistance and conductivity are opposite properties. While resistance measures the hindrance of electrical flow, conductivity measures the ease of electrical flow. A material with high resistance will have low conductivity, and vice versa.
The three main factors that affect resistance are the material of the conductor, the length of the conductor, and the cross-sectional area of the conductor. Other factors such as temperature and the presence of impurities can also impact resistance.
In electrical circuits, resistance can limit the amount of current flowing through the circuit, which can affect the overall performance and efficiency of the circuit. Resistance can also cause the circuit to heat up, potentially leading to damage or malfunction.
Some examples of materials with high resistance include rubber, glass, and plastic. These materials are often used as insulators in electrical circuits to prevent current from flowing through them. Other materials with high resistance include wood, air, and certain types of ceramics.