Photoelectric Effect

minimum frequency that

the incident radiation must have in order to release electrons from the metal.

• minimum

  frequency.

• threshold

  frequency.

• wave

  frequency.

• cut off frequency

longest wavelength for the

liberation of electrons from the surface of a metal

• minimum wavelength

• maximum wavelength

• threshold wavelength

• longest wavelength

A single electron requires

a minimum energy Φ to escape the surface of the metal. This is called.........................

When a photon arrives at the metal plate, it may be captured by an electron. The electron gains all of the

photon’s energy and the photon no longer exists. Some of the energy is needed for the electron to escape

from the energy well; the rest is the electron’s ........................................

• potential energy

• kinetic energy

• elastic energy

• strain energy

Einstein’s photoelectric equation states that

Energy of a photon = ...................+ ........................ of electron

• work function + PE

• work function + KE

• threshold frequency + KE

• threshold wavelength + KE

Photons of energies 1.0 eV, 2.0 eV and 3.0 eV strike a metal surface whose work function is 1.8 eV.

State which of these photons could cause the release of an electron from the metal.

• 1.0 eV and 2.0 eV

• 2.0 eV and 3.0 eV

• 1.0 eV and 3.0 eV

• 1.0 eV, 2.0 eV and 3.0 eV