Question: The disparity between Planck's law and the Rayleigh-Jeans law led to what conclusion?
Answer: the picture given by classical physics is not duplicated by a range of results in the quantum picture

Question: Einstein and what other two individuals revisited the black-body problem in 1905?
Answer: Rayleigh and Jeans

Question: Who came up with the term, "ultraviolet catastrophe"?
Answer: Paul Ehrenfest

Question: When did Paul Ehrenfest come up with the name "ultraviolet catastrophe"?
Answer: 1911

Question: When was the first Solvay Conference held?
Answer: 1911

Question: Who received the Nobel Prize in Physics in 1918?
Answer: Max Planck

Question: What did Rayleigh & Jeans and Einstein prove independently in 1905?
Answer: classical electromagnetism could never account for the observed spectrum

Question: What name did Paul Ehrenfest give to the proofs from Einstein and Rayleigh & Jeans?
Answer: the "ultraviolet catastrophe"

Question: What was the topic of the first Solvay Conference?
Answer: "the theory of radiation and quanta"

Question: In what year did Planck receive the Nobel Prize in Physics for his discovery of energy quanta?
Answer: 1918

Question: Who first observed the photoelectric effect?
Answer: Alexandre Edmond Becquerel

Question: When was the photoelectric effect first observed?
Answer: 1839

Question: Who published the first thorough investigation of the photoelectric effect?
Answer: Heinrich Hertz

Question: Who received the Nobel Prize in 1921 for his work on the photoelectric effect?
Answer: Einstein

Question: What did Einstein with the 1921 Nobel Prize for?
Answer: his work on the photo-electric effect

Question: What is the photoelectric effect?
Answer: the emission of electrons (called "photoelectrons") from a surface when light is shone on it

Question: Einstein's paper on the photoelectric effect earned him the Nobel Prize in what year?
Answer: 1921

Question: Einstein's photoelectric effect work was rewards as opposed to his work on what other topic?
Answer: relativity

Question: Before Einstein, electromagnetic radiation was considered to behave as what?
Answer: a wave

Question: What terms describe different types of radiation?
Answer: "frequency" and "wavelength"

Question: What other types of wave besides light has its own intensity?
Answer: sound

Question: What is the energy transferred by a wave in a given time called?
Answer: intensity

Question: Prior to Einstein's work, light behavior was modeled as what?
Answer: a wave

Question: What is the name for the amount of energy transfered by a wave in a given time?
Answer: intensity

Question: What portion of the photoelectric effect was in disagreement with the believed description of light behavior?
Answer: the energy account

Question: What does it mean for a light source to be more intense than another?
Answer: gives out more energy per unit time and per unit space

Question: What is emitted as a result of the photoelectric effect?
Answer: photoelectrons

Question: What does the kinetic energy of a photoelectron depend on?
Answer: the frequency

Question: What happens if the photoelectron's frequency is too low?
Answer: no photoelectrons are emitted at all

Question: What is the term used when photoelectrons act virtually at the same time?
Answer: multiphoton effect

Question: What type of energy due photoelectrons emitted due to the photoelectric effect have?
Answer: kinetic

Question: What factor of the initial light source does the energy of the photoelectrons depend on?
Answer: frequency

Question: When the photon energy is less than the work function of the material the light is shone upon, how many photoelectrons are emitted?
Answer: no photoelectrons are emitted at all

Question: If the photoelectric effect is occuring, increasing the intensity of the light source causes what?
Answer: more photoelectrons to be emitted with the same kinetic energy

Question: Who introduced the first quantized model of the atom?
Answer: Niels Bohr

Question: When was the first quantized model of the atom introduced?
Answer: 1913

Question: Why was the first quantized model of the atom introduced?
Answer: to overcome a major shortcoming of Rutherford's classical model

Question: In classical electrodynamics, a charge moving in a circle should do what?
Answer: radiate electromagnetic radiation

Question: Who modeled the atom in 1913, challenging Rutherford's model?
Answer: Niels Bohr

Question: What was predicted to happen to a nucleus-orbiting electron under Rutherford's model?
Answer: the radiation would cause it to lose energy and spiral down into the nucleus

Question: What statement did Bohr make about the electron of an atom, citing Planck's work?
Answer: an electron in a Bohr atom could only have certain defined energies

Question: Who introduced the reduced Planck constant?
Answer: Bohr

Question: What is the reduced Planck constant also known as?
Answer: the quantity

Question: Who helped to give the correct quantization rules for electrons in 1925?
Answer: Heisenberg

Question: Who helped to give the correct quantization rules for electrons in 1926?
Answer: Schrödinger

Question: According to Heisenberg and Schrödinger, the reduced Planck constant remains what?
Answer: the fundamental quantum of angular momentum

Question: Bohr introduced what value as the quantum of angular momentum?
Answer: the reduced Planck constant

Question: What incorrect belief did Bohr hold about the reduced Planck constant?
Answer: Bohr thought that this was the angular momentum of each electron in an atom

Question: What scientist used matrix mechanics to bring electron behavior in line with the Bohr model?
Answer: Heisenberg

Question: When was the Schrödinger wave equation proposed?
Answer: 1926

Question:  What measurable value obeys a similar rule of angular momentum?
Answer: time vs. energy

Question: What forces measurement attempts to choose between trade-offs, in quanta?
Answer: either-or nature of uncertainty

Question: What form do measurement attempt trade-offs for quanta take the form of?
Answer: either-or (as in Fourier analysis)

Question: How is uncertainly measured in this experience?
Answer: the standard deviation of the measured value from its expected value

Question: What type of analysis fits the either-or nature of the uncertainty?
Answer: Fourier analysis

Question: What example is given as another paired relationship of uncertainly related to standard deviation?
Answer: time vs. energy

Question: What is the unit of magentic properties of the electron?
Answer: Bohr magneton

Question: What is the unit of magentic properties of atomic nuclei?
Answer: nuclear magneton

Question: The Bohr magneton is the magnetic moment of an electron under what restriction?
Answer: behaved as a spinning charge according to classical electrodynamics

Question: What three terms define the Bohr magneton value?
Answer: the reduced Planck constant, the elementary charge and the electron mass

Question: How was the Planck constant calculated in the early 20th century?
Answer: the Planck constant could be determined by examining the spectrum of a black-body radiator or the kinetic energy of photoelectrons

Question: The value quoted here for the Planck constant is based on a measurement in what year?
Answer: 2007

Question: Where was this measurement made?
Answer: the U.S. National Institute of Standards and Technology (NIST)

Question: What method was was used to obtain the measurement?
Answer: watt-balance measurement

Question: One other measure involved the molar volume of what element?
Answer: silicon

Question: What is a main practical difficulty in determining n?
Answer: the two most accurate methods, the watt balance and the X-ray crystal density method, do not appear to agree with one another

Question: Why does this difficulty occur?
Answer: it is (or they are) not as precise as is currently believed