L3 Physics - Photoelectric effect # 3

the wavelength of a photon can be found using 

• λ = cf
• λ = hf
• λ = c/f
• λ = f/c

Light of a single wavelength is incident on a metal.  Electrons are released. The intensity of the light is then increased.
Which of the following changes occur?

• Rate of electron emission: increase.
  Energy of electrons: increase.
• Rate of electron emission: decrease.
  Energy of electrons: no change.
• Rate of electron emission: decrease.
  Energy of electrons: increase.
• Rate of electron emission: increase.
  Energy of electrons: no change.

The photoelectric effect is when:

• Electrons collide inside a metal to release photons.
• One incident metal electron releases one photon.
• One incident photon releases one electron from a metal.
• Photons are absorbed in to metal ions releasing electrons.

If the brightness of a beam of light increases without changing its color, the ______ will increase.

• number of photons

• frequency of the light

• energy of the photons

• wavelength of the photons

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

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

The energy of photoelectrons emitted from a metal surface can be increased by

• using light of higher frequency.

• using light of longer wavelength.

• using light of higher intensity.

• using monochromatic, polarized light.

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.