Physics Grade 12 Sheet

Which of the following exhibits very high resistance?

• insulator

• conductor

• semiconductor

• superconductor

A valence electron is an electron

• in the outermost shell of an atom

• that is no longer bound to the atom.

• in an atom’s excited state.

• in an atom’s ground state.

When identical atoms are far apart, they have energy-level diagrams and wave functions.

• split; split

• identical; identical

• different; different

• level; split

When an n-type semiconductor and a p-type semiconductor are brought together to form a p-n junction, electrons from the layer diffuse toward the layer, and positive holes are formed in the layer.

• n; p; n

• p; n; p

• p; n; n

• n; p; p

Which statement about a p-n junction is NOT correct?

• It will allow current to flow in a circuit in either direction

• The holes and electrons on either side of the p-n junction can migrate across the junction.

• Electrons from the n side nearest the junction diffuse toward the p side

• On the p side nearest the junction, electrons diffuse so that holes move to the inside.

Which solid has an empty conduction band and a full valence band?

• conductor

• semiconductor

• insulator

• superconductor

Which of the following exhibits zero resistance below a critical temperature?

• insulator

• conductor

• semiconductor

• superconductor

Electrons are NEVER free to move within a solid and carry electric current in a(n)

• insulator

• conductor

• semiconductor

• superconductor

Which solid has a full valence band and a small energy gap?

• conductor

• semiconductor

• insulator

• superconductor

The circuit symbol shown is for a(n)

• n-p-n transistor

• p-n-p transistor

• rectifier

• diode