Conductors and Insulators

Which of these materials is a good electrical insulator?

• Sea water

• Gold

• Glass

• Copper

Which material has three valence electrons?

• Copper

• Magnesium

• Aluminium

• Gold

What is the typical number of valence electrons in semiconductor atoms?

• Two

• Four

• Six

• Eight

Which elements are commonly found in semiconductors?

• Oxygen, nitrogen, and hydrogen

• Carbon, silicon, and germanium

• Iron, copper, and aluminum

• Helium, neon, and argon

What unique property do semiconductors have?

• Ability to conduct heat

• Ability to switch between conducting and insulating states

• Ability to absorb water

• Ability to emit sound

Why do insulators have low electrical conductivity?

• They have many free electrons

• They have very few or no free electrons

• They have high thermal conductivity

• They have a metallic structure

What is the role of valence electrons in insulators?

• They are free to move

• They are strongly bound to parent atoms

• They conduct electricity

• They are easily excited

What is the function of the jacket in a cable?

• To conduct electricity

• To provide mechanical protection

• To increase current flow

• To enhance conductivity

What is the function of the fluorescent coating in a discharge lamp?

• To provide structural support

• To emit light

• To conduct electricity

• To cool the lamp

Which component provides structural support in the discharge lamp?

• Solder

• Top Support

• Arc Tube

• Resistor