PHOTOELECTRIC EFFECT

Light of a given wavelength is used to illuminate the surface of a metal. However, no photoelectrons are emitted. In order to cause electrons to be ejected, light of __________ should be used.

• lower energy

• higher intensity

• shorter frequency

• higher frequency

What is the energy, in eV, of a photon that has a wavelength of 620 nm?

• 1eV

• 2eV

• 3eV

• 4eV

The energy of a photon is directly proportional to its _____ and inversely proportional to its ______.

• intensity - speed

• wavelength - frequency

• frequency - wavelength

• intensity - wavelength

In the photoelectric effect, if the incident photons have a wavelength that is larger than the threshold wavelength, _______.

• electrons will be ejected from the metal surface

• there will be photoelectric current

• no electrons will be emitted from the metal surface

• the kinetic energy of the ejected electrons increases

A metal with a work function of 3.5 eV is exposed to photons with an energy of 3.7 eV. What is the maximum kinetic energy of the emitted photoelectrons?

• 0.2 eV

• 0.9 eV

• 1.1 eV

• 7.7 eV

A particle of light is called a...

• Photoelectron

• Photon

• Proton

• Electron

The photoelectric effect only occurs if the light shining on the metal is:

• coherent.
• above a minimum intensity.
• above a minimum frequency.
• above a minimum wavelength.

What is the best description of 'threshold frequency'?

• The minimum energy needed for electrons to escape a surface.

• The maximum kinetic energy that an emitted electron has.

• The minimum frequency of a photon that will cause an electron to be emitted.

• The frequency that an emitted electron will have.

What is the maximum kinetic energy of electrons emitted from caesium (Cs), when light of frequency 1x 10¹⁵ Hz falls upon the metal? (work function for Cs is 2.0eV)

• 8.0x10^-19 J

• 4.0 eV

• 2.0 x10^-19 J

• 2.0 eV

What did Max Planck tell about light?

• Light travels in the form of small packets of energy called photons.

• Light travels in the form of small packets of energy called quanta.

• Light travels in the form of electromagnetic radiation.

• Light is made up of tiny particles called corpuscles.