1. Light Wave or Particle?

2. Evidence
Wave Properties
Particle Properties

3. Interference of Light
When two light waves hit they _______________________________ each other.
While they occupy the same space the waves _______ amplitudes and frequencies to produce a different wave. This is called _______________________.
If two _________ hit they bounce off each other. They don’t interfere like waves.

4. Refraction & Dispersion of Light
When light enters glass it _________.
This is called ____________
How much light refracts depends on the type of _____ and the ____ of light.
A particle could refract, wave theory works better.
When _________ light enters glass the different frequencies bend differently.
This causes the light to split into the ____________.
This is called ______________.
Particles wouldn’t display dispersion.

5. The Doppler Effect for Light
When a light source is moving the frequency of light it emits changes due to this _____________.
A particle doesn’t do this, only a _____________.

6. Diffraction of Light
You get a _________________, called a _______________________ pattern.
Basically the light __________ as it _________ the slit causing an alternating series of constructive and destructive interference.
A particle wouldn’t do this.
If I fire this laser through a small slit, what will I see on the wall when it hits?

7. The Photoelectric Effect
When light hits certain metals it causes the metal to eject ______________.
Treating light as a wave tells us that the __________ the light, the more electrons get ejected or the electrons get ejected at a ________________.
This would be true if it wasn’t__________!!!
It turns out the ______________ of the light is what determines whether or not electrons are ____________ from the metal.
This suggests that light travels in _________ or packets called _______ which behave like particles.

8. The Ultraviolet Catastrophe
A blackbody radiator absorbs all electromagnetic radiation that hits it and emits its own electromagnetic radiation based on its ___________.
Wave theories predict that the wavelengths of electromagnetic waves a blackbody will emit should follow the relationship shown by the ___________________ in the graph.
It turns out that experiments show that the wavelength of electromagnetic waves emitted by a blackbody actually follow the ______________ shown in the graph called blackbody curves.
Which curve is determined by the temperature of the blackbody.

9. The Ultraviolet Catastrophe
This also suggests that light travels in _______ or packets called ______ which behave like ________.

10. The dual nature of light