GED Science TestPhysical ScienceEasy
An engineer is designing a circuit for a new electronic device. They need to select a material that will allow electric current to flow easily through it. Which property is most important for this selection?
- AHigh resistivity
- BHigh conductivity
- CLow density
- DLow thermal expansion
Show answer & explanationAnswer & explanation
Correct answer: B. High conductivity
High electrical conductivity is the ability of a material to allow electric charge to flow easily through it. This is essential for materials used in electrical circuits to transmit current.
Why the other options are wrong
- A. High resistivity means the material resists current flow, making it an insulator, which is the opposite of what is needed.
- C. Low density is a measure of mass per unit volume and is not directly related to electrical current flow.
- D. Low thermal expansion refers to how much a material changes in size with temperature, not its electrical properties.
Electrical Conductivity
A measure of a material's ability to conduct an electric current, which is the inverse of resistivity.
- Good conductors have high conductivity (e.g., metals).
- Poor conductors (insulators) have low conductivity.
- Measured in Siemens per meter (S/m).
Memory trick: Electricity's path: some let it flow, some make it slow.