Terms in this set (17)
In experiments examine the photoelectric effect, the kinetic energy of the ejected electrons depends on
the frequency of the light photons, the threshold frequency, the work function
In the photoelectric effect, for light that is above the threshold frequency for a given metallic surface, increasing the intensity of the light incident on a metal surface
increases the current of the photoelectrons
A distant star moving toward Earth emits light that is 600nm but we receive this light as being 400nm long. We would view light as
Paula travels at high speed from Earth to the star Alpha, four light years ways as measured from Earth. What does Paula experience in her frame of reference?
Paula travels to Alpha over a length shorter than 4 light years
The ether wind is a hypothetical medium through which EM waves were thought to travel. Whose experiments proved that it doesn't exist
Michelson and Morley
What happens when an observer in moving inertial frame of reference measures time in a stationary inertial frame of reference
Time in other frame runs slower
Which statement about blackbody radiation is false
A hotter blackbody emits lower frequency radiation
A spaceship approaching Earth at 0.8c measured relative to Earth. The spaceship directs a laser beam forward directly through your physics classroom window. You measure the speed of light to be
The sun emits huge amounts of energy in the forms of thermal energy and light. What is the source of this energy?
Mass transforming into energy as lighter nuclei fuse into heavier nuclei inside the Sun
What affect does intensity have on the threshold frequency?
Intensity of the light has no effect on the threshold frequency
What does threshold frequency mean?
Threshold frequency in the minimum frequency required for electrons to be emitted from the surface
Would light that produces a photocurrent in caesium also produces a photocurrent in copper?
No because different metals have different threshold frequencies. Some metals have a stronger hold on their electrons
If you were on a spaceship moving away from the Earth at 0.9c, what changes would you observe in your shoe size, height, your mass or your pulse rate? What specific changes would an observer watching you from the Earth with a telescope note in these quantities?
You would not observe any changes. An observer on the other hand would notice a decrease in shoe size, same height, increase in mass, and a decrease in pulse
What is the relationship between temperature and frequency of the EM radiation emitted?
As temperature increases so does frequency
What does the phase red hot mean?
When an object is in the red EM radiation emitted the object glows a red colour
Is it possible that EM radiation is being emitted, yet we can't see it?
Yes it is possible because the human eye is only able to see visible light and infrared or UV rays emitted are not seen
What is the "ultraviolet catastrophe" and how was it solved?
As the temperature increases so does the intensity except in the UV section. This is called the UV catastrophe. This was solved when Planck said light was quantitized