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36 questions
The graph shows how the maximum kinetic energy Ek of photoelectrons emitted from a metal surface varies with the reciprocal of the wavelength λ of the incident radiation.
What is the gradient of this graph?
c
h
hc
h/c
Photons of wavelength 290 nm are incident on a metal plate. The work function of the metal is 4.1 eV
What is the maximum kinetic energy of the emitted electrons?
0.19 eV
4.3 eV
6.9 eV
8.4 eV
Which statement suggests that electrons have wave properties?
Electrons are emitted in photoelectric effect experiments.
Electrons are released when atoms are ionised.
Electrons produce dark rings in diffraction experiments.
Electron transitions in atoms produce line spectra.
When light of a certain frequency greater than the threshold frequency of a metal is directed at the metal, photoelectrons are emitted from the surface. The power of the light incident on the metal surface is doubled.
Which row shows the effect on the maximum kinetic energy and the number of photoelectrons emitted per second?
Maximum kinetic energy: remains unchanged
Number of photoelectrons emitted per second: remains unchanged
Maximum kinetic energy: doubles
Number of photoelectrons emitted per second: remains unchanged
Maximum kinetic energy: remains unchanged
Number of photoelectrons emitted per second: doubles
Maximum kinetic energy: doubles
Number of photoelectrons emitted per second: doubles
Line X on the graphs below shows how the maximum kinetic energy of emitted photoelectrons varies with the frequency of incident radiation for a particular metal.
Which graph shows the results for a metal Y that has a higher work function than X?
A beam of light of wavelength λ is incident on a clean metal surface and photoelectrons are emitted. The wavelength of the light is halved but energy incident per second is kept the same.
Which row in the table is correct?
Maximum kinetic energy of the emitted photoelectrons: Increases
Number of photoelectrons emitted per second: Unchanged
Maximum kinetic energy of the emitted photoelectrons: Decreases
Number of photoelectrons emitted per second: Increases
Maximum kinetic energy of the emitted photoelectrons: Increases
Number of photoelectrons emitted per second: Decreases
Maximum kinetic energy of the emitted photoelectrons: Decreases
Number of photoelectrons emitted per second: Unchanged
In an experiment to demonstrate the photoelectric effect, a charged metal plate is illuminated with light from different sources. The plate loses its charge when an ultraviolet light source is used but not when a red light source is used.
What is the reason for this?
The intensity of the red light is too low.
The wavelength of the red light is too short.
The frequency of the red light is too high.
The energy of red light photons is too small.
Electromagnetic radiation incident on a metal surface can cause electrons to be emitted.
Which of the following statements is correct?
Every photon incident on the surface causes an electron to be emitted.
All the emitted electrons have the same energy.
The range of energy of the emitted electrons depends on the intensity of the radiation.
If the incident radiation is of a single frequency, the number of electrons emitted per second increases if the intensity of the radiation increases.
When comparing X-rays with UV radiation, which statement is correct?
X-rays have a lower frequency.
X-rays travel faster in a vacuum.
X-rays do not show diffraction and interference effects.
Using the same element, photoelectrons emitted using X-rays have the greater maximum kinetic energy.
Monochromatic radiation from a source of light (source A) is shone on to a metallic surface and electrons are emitted from the surface. When a second source (source B) is used no electrons are emitted from the metallic surface. Which property of the radiation from source A must be greater than that from source B?
amplitude
frequency
intensity
wavelength
In a photoelectric experiment, light is incident on the metal surface of a photocell. Increasing the intensity of the illumination at the surface leads to an increase in the
work function
minimum frequency at which electrons are emitted
current through the photocell
speed of the electrons
A particle of light is called a...
Photoelectron
Photon
Proton
Electron
The only way to increase the number of photoelectrons emitted is by increasing the _________ of the light
Intensity
Wavelength
Frequency
Energy
What color of light has the greatest energy per photon?
Red
Green
Blue
Violet
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.
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.
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