Week 3 Lecture 11
Solutions at the bottom.

1)  In-video quiz at timepoint 05:36.

"In the physical sciences, a particle is a small localized object to which can be ascribed several physical or chemical properties such as volume or mass."

- Wikipedia, Particle, http://en.wikipedia.org/wiki/Particle

"In physics, a quantum (plural: quanta) is the minimum amount of any physical entity involved in an interaction. Behind this, one finds the fundamental notion that a physical property may be "quantized," referred to as "the hypothesis of quantization". This means that the magnitude can take on only certain discrete values."

- Wikipedia, Quantum, http://en.wikipedia.org/wiki/Quantum

"A photon is an elementary particle, the quantum of light and all other forms of electromagnetic radiation, and the force carrier for the electromagnetic force, even when static via virtual photons."

- Wikipedia, Photon, http://en.wikipedia.org/wiki/Photon

2)  In-video quiz at timepoint 24:48.

Which of the following determines the amount of energy in a photon of light? 

a) Wavelength
b) Frequency
c) Amplitude
d) Velocity

Solutions:

2) The correct answer is: b) Frequency

E = hf

The energy of an electromagnetic wave (a photon) is determined only by its frequency.  In a vacuum, we can use the equation f λ = c to relate photon energy to wavelength, but this will not strictly hold true if the light is traveling in a non-vacuum (such as air, water, glass, diamonds, etc...).