conductors and insulators

1. Metals are good conductors of electricity because:

• In metals there are many free nuclei

• In metals there are many free atoms.

• In metals there are many free electrons.

• In metals there are many nuclei, atoms and free electrons.

2. In metals, free electrons are electrons

• revolve around the nucleus.

• can move from one position to another

• escape from the atom and move freely in the metal

• directional movement

Lightning is caused by electrical charges moving very quickly through the air. In this case the air there

• generate an electric current

• glow

• become a conductive material

• heated up

Conductors are substances:

• capable of passing current

• capable of allowing positively charged particles to pass through

• capable of allowing negatively charged particles to pass through

• Sentences A, B, and C are all correct.

 Which of the following objects is an insulator?

• Glass, rubber, wood

• Iron, copper, aluminum

• Salt water, lemon juice

• Gold and silver

Choose the sentence that arranges the substances according to their increasing ability of good electrical insulators

• Air, plastic, porcelain

• Distilled water, glass, plastic

• Rubber, dry wood, porcelain

• Air, glass, plastic

Which of the following materials is an insulator?

• Wood

• Copper

• Iron

• Aluminum

Choose the correct answer

When doing electrical repairs in the house, Poles often stand on wooden or plastic chairs. Do so to:

• No contact with the ground

• Avoid electric shock

• Do not allow electric current to pass through people

• All three sentences are correct

Choose the correct explanation Why are electric wire cores usually made of copper?

• Because copper is easy to spin, malleable and malleable

• Because copper conducts electricity well

• Because copper is a fairly common material, the price is not too expensive compared to other good conductive materials

• Both the a, b, c are correct

Choose the sentence that arranges substances according to their increasing ability to conduct electricity

• Common water, copper, mercury

• Common water, graphite, gold

• Mercury, salt solutions, iron

• Silver, acidic solutions, graphite