Material Conductivity

Which of the following is not a good conductor of electricity?

• Aluminium

• Copper

• Steel

• Wood

What is the current passing through a load of 10 ohms when a voltage of 20 volts is applied in a dc circuit?

Which of the following materials is commonly used as an insulator?

• Rubber

• Gold

• Copper

• Aluminium

What is the primary reason metals are good conductors of electricity?

• Low melting point

• Low atomic mass

• High density of electrons

• High thermal resistance

Which of the following is a property of semiconductors?

• They have a fixed resistance

• They conduct electricity at all temperatures

• They are always insulators

• They can conduct electricity under certain conditions

What is the effect of temperature on the conductivity of semiconductors?

• Conductivity is constant at all temperatures

• Temperature has no effect on conductivity

• Conductivity decreases with temperature

• Conductivity increases with temperature

Which of the following is a characteristic of superconductors?

• They conduct electricity only at high temperatures

• They have a high melting point

• They are always insulators

• They have zero electrical resistance

What is the primary reason why non-metals are generally poor conductors of electricity?

• High melting point

• High thermal conductivity

• High atomic mass

• Low density of electrons

What is the main characteristic of conductors compared to insulators?

• They allow the flow of electric current

• They are always metals

• They have high resistance

• They have low thermal conductivity

Which of the following elements is typically used in electrical wiring due to its conductivity?

• Silver

• Iron

• Plastic

• Glass