Questions by Mike Usher and editors—round 5
1. As a mathematical adjective, it refers to vector bundles whose first two Stiefel-Whitney classes are zero and to the group which is a double cover of the special orthogonal group. In physics, its relevance to quantum mechanics was first suggested by Ralph Kronig, but Wolfgang Pauli's ridicule convinced him not to publish, so George Uhlenbeck (pron. OOH-len-beck) and Samuel Goudsmit (pron. GOOD-shmit) generally receive the credit. FTP, name this quantity which Pauli later proved to be related to statistics, which is an integer for bosons and a half-integer for fermions.
Ans: spin
2. The author refutes the claim that that there's more water than land on Earth, pointing out that if that were the case then all the land would be completely submerged. The body of the work begins by explaining that the universe is spherical because the sphere is the most perfect of all forms, a Platonist attitude which is also reflected in the book's epigraph, "Let no one untrained in geometry enter here." FTP, name this work published just before its author's 1543 death which argued for a heliocentric theory of the solar system.
Ans: De Revolutionibus Orbium Coelestium or On the Revolutions of Heavenly Spheres
3. In one version of this reaction, either a carbonium ion or an alkyl-hydrogen sulfate is formed as an intermediate and is converted into an oxonium ion, which then loses a proton to yield the product. Another version is a nucleophilic substitution in which an alkoxide ion displaces the halide ion in a haloalkane. FTP, name this reaction in which an alcohol is converted into an ether.
Ans: Williamsonether synthesis
4. This organelle contains the enzyme AGT, whose malfunction results in the excess production of oxalate, causing kidney stones, while problems with the organelle's assembly lead to Zellweger's syndrome. Refsum disease results from its failure to break down phytanic acid, but its most important function is probably the oxidation of long-chain fatty acids. FTP, name this single membrane organelle which contains several enzymes that produce hydrogen peroxide as a byproduct.
Ans: peroxisome
5. Every node is one of two kinds (let's call them "A" and "B"). The root node is of kind A. Leaf nodes are also A. The parent of any B must be an A. Every direct path from a node to a leaf must contain the same number of A points. These are the five invariants for, FTP, what colorful data structure, a binary tree that remains more or less balanced after insertions and deletions?
Ans: red-black tree
6. Consequences of this law include the Kutta-Zhukovski Theorem and d'Alembert's paradox, the latter of which notes that in the absence of a boundary layer the drag on any object in irrotational flow is zero. It can be derived by integrating Euler's equation for inviscid motion along a streamline, though its namesake derived it directly from conservation of energy. FTP, name this law which partly explains how the wing of an airplane works and implies that decreasing the pressure on a fluid increases its speed.
Ans: Bernoulli's law (or principle, equation, etc.)
7. The Coriolis force splits their eigenfrequencies. Measurements of their periods can be used to extend the dispersion curves for surface waves. Toroidal ones correspond to Love waves, spheroidal ones correspond to Rayleigh waves. Slichter modes correspond to inner core translation, and research suggests that they can trigger aftershocks. FTP, name these allowed vibrations of the Earth which ring for days after strong earthquakes.
Ans: free oscillations or normal modes of the Earth
8. First proposed by Lewis, it corrects a gas’s standard Gibbs free energy by adding this quantity multiplied by the gas constant and temperature. The ratio of this quantity to some standard state is called the activity. This quantity is used in place of partial pressures in reactions that involve real gases. Describing the tendency of a substance of a substance to escape from its current phase. FTP, name this thermodynamic quantity, symbolized by f.
Ans: fugacity
9. His interpretation of the Jones knot invariant as a statistical average, his simplification of Schoen and Yau's proof of the positive mass theorem, and his discovery of the relation between gradient flow lines and the Morse complex helped earn him a 1990 Fields Medal. More recently, he has explored the relationship between K-theory and D-brane charges, and he and Nathan Seiberg jointly derived their important monopole equations in 1994. FTP, name this leading authority on M-theory and string theory.
Ans: Edward Witten
10. The liver usually synthesizes 1.5 to 2 grams of it per day due to its role in the production of bile acids, though drugs that block the action of HMG-CoA reductase, such as lovastatin, are often used to slow its production. Vitamin D is derived from this compound upon exposure to ultraviolet light; its other important roles include breaking up van der Waals interactions in order to increase the fluidity of the cell membrane and serving as a precursor to steroid hormones. FTP, name this molecule, whose LDL form deposits in arterial walls, causing arteriosclerosis.
Ans: cholesterol
11. He worked with Einstein on a refrigerator without moving parts, inventing a pump named for him and Einstein. He filed the first British patent on the neutron chain reaction, and designed his own radiation treatment when he was diagnosed with bladder cancer, of which he successfully cured himself. Remembered for his advocacy and social conscience, FTP name this Hungarian who helped draft a letter to Roosevelt advocating the construction of the atomic bomb, but later opposed the development of the hydrogen bomb.
Ans: LeoSzilard
12. It occurs in materials with a small positive susceptibility, including chromium and aluminum. When a small fraction of the permanent atomic dipoles are aligned with the external field it obeys Curie’s law, scaling as one over temperature at high temperatures. It increases with the applied magnetic field until saturation. Weaker than ferromagnetism, FTP name this phenomenon in which a material reinforces the ambient magnetic field.
Ans: paramagnetism
13. Identified in the 1970s by Carl Woese, a cladistic analysis based on genotype separated this group from its previously closely related relatives. Unique features include branching of membrane lipids, several unique RNA polymerases, and the lack of peptidoglycans in their cell walls. Consisting mostly of thermophiles, halophiles, and methanogens, they arose approximately 3.5 billion years ago. FTP, name this kingdom of bacteria-like organisms that are the possible bridge organisms to eukaryotes.
Ans: KingdomArchaea or Archaebacteria
14. The first precipitate to form as seawater evaporates, it exhibits rhomboidal cleavage, and has the same chemical composition as aragonite, but is more stable. It is formed from the shells and skeletons of foraminifera and other organisms. A positive result on the acid test usually indicates the presence of this mineral, whose crystals are birefringent (pron. by-ree-FRIN-jent). The primary mineral component of marble and limestone, FTP name this calcium carbonate mineral.
Ans: calcite
15. Researchers in Canberra conducted an experiment with latex beads and lasers showing that it can be violated for short time scales. It was introduced in an 1850 paper refuting caloric theory written by Clausius, but the traditional statement is the Kelvin-Planck formulation, which states that it is impossible for a cyclic process to completely convert heat from a reservoir into useful work with no other effect. FTP, what is this law which states that the entropy of a closed system increases over time?
Ans: second lawofthermodynamics
16. This biome was much more prevalent during the Pleistocene Epoch in North America, but gradually decreased in extent as temperatures became more extreme and droughts increased. Home to large herds of grazing mammals, 90 to 150 centimeters of rain fall each year in this biome. A transition between tropical rain forest and desert, FTP, name this biome most prevalent in Sub-Saharan Africa consisting of arid open grassland.
Ans: savanna
17. An isopleth through it passes from liquid to solid, usually lamellar, at a single temperature of the same name. The zero point of the Fahrenheit scale was defined as the temperature at this point for a mixture of salt and ice. Binary mixtures where the components are soluble in the liquid state but insoluble in the solid state will have two liquidus curves which meet at this point. FTP, what is this minimum freezing point for a set of components?
Ans: eutectic point
18. Early observational work by McLaughlin and Payne-Gaposchkin suggests that they might be periodic. Most models are based on a binary system with a lobe-filling ordinary companion. Unresolved questions include whether the mass-transfer process can push the involved star past the Chandrasekhar limit. Triggered by a thermonuclear explosion on the surface of a white dwarf, FTP name this type of cataclysmic variable eruption.
Ans: novae
19. Given an 2-dimensional image, perhaps representing a pattern, and another image -- usually a projection of a 3-dimensional object, use the 2-d image as a lookup table in drawing the 3-d object: whenever a pixel in the object is about to be plotted, look up the corresponding coordinates in the 2-d image to determine what color to make the pixel. FTP, this describes what computer graphics technique for "pasting" images onto surfaces?
Ans: texture mapping
20. This type of interaction is given a misleading name because it is really the hydrogen bonding of water that causes hydrocarbons to join together. Nonpolar covalent bonds do not interact with the charges of polar covalent bonds. Hence butane and oil will not dissolve in water. Instead, when hydrocarbons are dispersed in water, they slowly come together, forming larger and larger droplets. FTP, name this type of interaction literally meaning "water-fearing."
Ans: hydrophobicinteraction
1. Answer the following about a class of substances which includes detergents and soaps, FTP each:
10) This is the term for a molecule, usually partly hydrophobic and partly hydrophilic, which functions to reduce the surface tension in liquids.
Ans: surfactant or surface-active agent or amphipathic
10) When a high concentration of a surfactant is present in water, the surfactant molecules often align themselves into a spherical structure with the hydrophobic portions pointing toward the center. What is the name for this structure?
Ans: micelle
10) Sodium dodecyl sulfate and lecithin are both surfactants that aid in the conversion of two immiscible layers of liquid into this type of colloid.
Ans: emulsion
2. Give the following terms related to unconsolidated rock, FTP each:
10) Sometimes used synomously with scree, this term refers to the slope of rock debris that forms at a 35 degree angle at the base of a peak.
Ans: talus
10) This term refers to the layer of unconsolidated rock lying above the bedrock, and also to the layer of rock fragments that, due to meteorite impacts, covers most of the surface of the moon and other objects in the solar system.
Ans: regolith
10) Not to be confused with a Watergate-era organization, this slowest unconsolidated mass movement is the downhill movement of regolith due to gravity.
Ans: creep
3. Answer the following about the vector quantity whose curl is the magnetic field, FTP each:
10) Name this quantity, usually symbolized by a capital A.
Ans: magnetic vector potential
10) In order to determine the vector potential uniquely, one needs to "fix a gauge" by specifying its divergence. What physicist gives his name to the gauge in which the divergence of the vector potential is zero?
Ans: Charles Coulomb
10) Although the vector potential is usually thought of as only an artificial construction, in this effect the vector potential influences the motion of electrons outside a long solenoid even in locations where there is no magnetic field.
Ans: Aharonov-Bohm or Bohm-Aharonoveffect
4. Name the following people who made discoveries related to DNA FTPE.
10) This man discovered DNA in the nuclei of pus cells from discarded surgical bandages in 1868.
Ans: Friedrich Miescher
10) In 1950, this Columbia biologist observed that the DNA of any organism contained equal amounts of cytosine and guanine and equal amounts of adenine and thymine.
Ans: Erwin Chargaff
10) DNA was definitively confirmed to be the genetic material in a 1952 experiment using bacteriophages which had grown in cultures in which either the sulfur or the phosphorus was radioactive. FTP, all or nothing, name the two scientists responsible.
Ans: Alfred Hershey and Martha Chase
5. Identify these mathematicians whose names are attached to fixed-point theorems, FTPE.
10) This Dutchman proved that any continuous map from the disk to itself has a fixed point, but later disavowed his topological work after rejecting the principle of the excluded middle.
Ans: Luitzen Egbertus Jan Brouwer
10) This mathematician generalized the Brouwer fixed point theorem to show that there exists a fixed point for any upper semicontinuous correspondence from a convex compact set to itself such that each point has a nonempty compact image.
Ans: Shizuo Kakutani
10) This Frenchman's eponymous "last geometric theorem," left unresolved at his death and proven in 1925 by George Birkhoff, states that any area-preserving twist map of the annulus has two fixed points. He also introduced the idea of the fundamental group of a space. Ans: Jules Henri Poincare
6. Name the following things relating to the Sun's atmosphere FTPE.
10) The presence of this element was first revealed by study of the emission lines in a flash spectrum of the chromosphere taken during a solar eclipse.
Ans: Helium
10) Often considered the surface of the Sun, it has a temperature of about 5800 Kelvin. Photons in this layer make a transition from random walk to flying free.
Ans: photosphere
10) In this phenomenon, the edge of the Sun appears darker than its center, because for the same optical path length, the path towards the center penetrates to deeper, hotter layers.
Ans: limb darkening
7. Name these things related to plasmas FTPE.
10) Proposed by Igor Tamm to hold plasma using magnetic fields, the first was built in the USSR and takes its name from the Russian words for "toroidal magnetic chamber."
Ans: tokamak
10) These oscillations in plasmas at the plasma frequency are named for the 1932 Chemistry Nobel Prize winner who first observed them.
Ans: Langmuirwaves
10) This stabilizing effect in ignited tokamak plasmas is named for a Russian Nobel Prize winner who studied condensed matter and low temperature physics.
Ans: Landau damping
8. Identify the following related to molecular markers of cancer FTPE.
10) A blood test for elevated PSA levels often is an early detector of this particular type of cancer.
Ans: prostatecancer
10) The BRCA1 gene is overexpressed in a large population of patients with this type of cancer.
Ans: breastcancer
10) Mutations in this gene, which is normally responsible for cell cycle arrest and apoptosis (ay-pop-TOH-sis), appear in over 50% of all human cancers, especially in prostate and breast cancer.
Ans: p53
9. Answer these questions about electrons in orbitals FTPE.
10) Starting with the 2s orbital, every orbital contains a region of zero electron density. This region is sphere-shaped in s orbitals and is a plane in p orbitals. Name the term common to the sphere or the plane.
Ans: node or nodal plane
10) The three 2p orbitals differ only in their spatial orientation, so they have identical energies. Name the term that describes orbitals with identical energies.
Ans: degenerate orbitals
10) This concept describes the spin-pairing effect that causes orbitals to hold a maximum of 2 electrons. No two electrons thus can have the same set of quantum numbers.
Ans: Pauli exclusion principle
10. Answer the questions about memory management FTPE.
10) An early solution to the problem of programs that were too big to fit in the computer's memory, this technique required the programmer to manually divide her program into smaller parts that called each other.
Ans: overlays
10) This technique allows part of the hard disk to be used as memory; the operating system automatically swaps data back and forth between the disk and the physical memory.
Ans: virtual memory
10) When a program tries to use data that is not in memory, this type of exception occurs, allowing the operating system to fetch the data.
Ans: page fault
11. Identify the following things about four-vectors FTPE.
10) The three components of momentum form a four-vector with this scalar quantity.
Ans: energy
10) For a position four-vector, if x squared plus y squared plus z squared is greater than c squared t squared, then the four-vector is described by this term.