HS Sample Set 12, Round 11 from NSB
A 50-kilogram mass is sliding at an initial speed of 5.25 meters per second on ice, coming to rest uniformly in 3.5 seconds due to friction. In newtons, what is the magnitude of the force of friction on the mass due to the ice?
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Gloria is preparing to image a biological sample, so she places it underneath a 50-millimeter glass slide. Given that the index of refraction of the glass is 1.2 and that she is viewing the sample from directly overhead, then, to the nearest whole millimeter, what is the apparent depth of the sample?
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Berkeley Lab researchers used broad-spectrum infrared light to determine the reactivity of a heterogeneous catalyst at different points on the surface of the catalyst. What user facility at Lawrence Berkeley National Lab did they use to generate the infrared light?
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Scientists at Oak Ridge National Lab have discovered a new method to filter out heavy isotopes of hydrogen using a functionalized form of what class of polymeric compounds, which consist of artificially-constructed porous carbon-based scaffolds ligating metal ions?
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When fermentation occurs in humans, pyruvate is reduced by NADH to form what molecule?
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What flexible amino acid is present on nearly every third residue of collagen, due to its ability to fit on the inside of the triple helix?
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What is the hybridization of the central atom in bromine trifluoride?
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Consider the combustion reaction of solid graphite with gaseous oxygen to generate gaseous carbon monoxide. Identify all of the following three changes that would shift the equilibrium of this reaction to the right: 1) Adding more solid carbon 2) Increasing the temperature 3) Compressing the reaction vessel
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According to the rational root theorem, which of the following is NOT a possible solution to the equation $$8x^3 - 2x^2 + x - 12 = 0$$? W) 2 X) 4 Y) 6 Z) 8
W: W) 2
X: X) 4
Y: Y) 6
Z: Z) 8
Answer: Z) Z) 8
A line contains five points A, B, C, D, and E. A second line contains four other points W, X, Y, and Z. What is the maximum possible number of lines that contain at least two of these 9 points?
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What isotope accounts for approximately 7 parts per trillion of the Earth’s atmosphere, and can be formed from the radioactive decay of tritium?
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Identify all of the following three minerals that have cubic crystal structure: 1) Calcite 2) Galena 3) Mica
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Steve is constructing an array from two antennas. He sets them to transmit in phase at 30 kilohertz, and he wants to place them in such a way that no destructive interference occurs at any location. To the nearest kilometer, what is the maximum separation distance between the antennas?
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A 7.2-kilogram box is sliding along a frictionless surface at 3 meters per second when it runs into a spring of spring constant 8,000 newtons per meter. In meters, how much will the spring be compressed?
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Which of the following ions has the smallest radius? W) Magnesium two plus X) Fluorine minus Y) Aluminum three plus Z) Sodium plus
W: W) Magnesium two plus
X: X) Fluorine minus
Y: Y) Aluminum three plus
Z: Z) Sodium plus
Answer: Y) Y) Aluminum three plus
Identify all of the following three orbitals that have two or more radial nodes: 1) 4d-xy 2) 5p-x 3) 3s
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Scientists at Brookhaven National Lab are studying molecular wires as a potential polymeric replacement for silicon-based technologies. Which of the following polymers could behave as a molecular wire without any other functional groups? W) Polyester X) Polyphenylene vinylene Y) Polyamide Z) Polystyrene
W: W) Polyester
X: X) Polyphenylene vinylene
Y: Y) Polyamide
Z: Z) Polystyrene
Answer: X) X) Polyphenylene vinylene
To better understand matter-antimatter asymmetry in the universe, scientists at SLAC are studying the CP-violating decays of what particle in the BaBar experiment?
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What part of a myelinated neuron is covered by myelin sheaths?
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When triggered by inositol triphosphate, ions of what element are released as second messengers?
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The core of what planet in our solar system constitutes the largest fraction of the planet’s volume?
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What type of star is thought to be massive enough to fuse deuterium and lithium, but cannot sustain hydrogen fusion?
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An arithmetic sequence has fourth term 9 and ninth term 29. What is the positive difference between consecutive terms for the sequence?
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Suppose that $$x$$ is congruent to 3 mod 7. In the integers mod 7, what is $$x^7$$?
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In a heavy-water-moderated reactor, what is the momentum of a neutron, as a fraction of its original momentum, after it collides with the deuterium atom in a stationary heavy-water molecule?
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A beam of light whose wavelength is 600 nanometers in a vacuum passes into a medium with an index of refraction of 1.333. To the nearest integer multiple of ten nanometers, what is the new wavelength of the light?
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What is the limit as $$x$$ approaches 6 of the function with numerator $$x - 6$$ and denominator $$x^2 - 36$$?
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Given that $$\log_{10}2 = 0.301$$ and $$\log_{10}3 = 0.477$$, to three decimal places, what is $$\log_{10}45$$?
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A student prepares a saturated sodium chloride solution and then adds a few drops of 12-molar hydrochloric acid. Which of the following will occur? W) No visible changes will occur X) A large amount of gas will be evolved Y) A hydrogen chloride precipitate will form Z) A sodium chloride precipitate will form
W: W) No visible changes will occur
X: X) A large amount of gas will be evolved
Y: Y) A hydrogen chloride precipitate will form
Z: Z) A sodium chloride precipitate will form
Answer: Z) Z) A sodium chloride precipitate will form
Which of the following best explains why mercury in a glass tube forms a convex meniscus? W) Mercury is repelled by the negatively-charged glass surface X) Mercury is more polar than the glass surface Y) Mercury is highly viscous Z) Mercury’s cohesive forces are stronger than its adhesive forces
W: W) Mercury is repelled by the negatively-charged glass surface
X: X) Mercury is more polar than the glass surface
Y: Y) Mercury is highly viscous
Z: Z) Mercury’s cohesive forces are stronger than its adhesive forces
Answer: Z) Z) Mercury’s cohesive forces are stronger than its adhesive forces
Which of the following correctly describes the weather phenomenon rime? W) Frozen fog deposit X) A tornado that spins clockwise in the Northern Hemisphere Y) High altitude lightning Z) Out-of-season hurricane
W: W) Frozen fog deposit
X: X) A tornado that spins clockwise in the Northern Hemisphere
Y: Y) High altitude lightning
Z: Z) Out-of-season hurricane
Answer: W) W) Frozen fog deposit
In which of the following locations could a paleontologist hope to find sedimentary rocks containing trilobites? W) Iceland X) The Canary Islands Y) Southern Florida Z) Manitoba
W: W) Iceland
X: X) The Canary Islands
Y: Y) Southern Florida
Z: Z) Manitoba
Answer: Z) Z) Manitoba
The common dandelion, which is fluorescent under UV light, is pollinated by what? W) Bees X) Wind Y) Butterflies Z) Moths
W: W) Bees
X: X) Wind
Y: Y) Butterflies
Z: Z) Moths
Answer: W) W) Bees
Your dog is suffering from chronic kidney disease. Identify all of the following that you would expect to see in his urine: 1) White blood cells 2) Glia 3) Protein
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Researchers at Lawrence Berkeley National Lab recently demonstrated that certain pore complexes can recognize and block aberrant strands of mRNA from entering the cytosol. In what membrane do these pore complexes reside?
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In order to image subsurface features, such as volcanic magma chambers, scientists at Pacific Northwest National Lab are investigating a strategy to use detectors for what high-energy leptons produced in cosmic ray showers?
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What is the complex conjugate of –7i?
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If a spherical balloon is inflated at a rate of $$\pi$$ cubic centimeters per second, at what rate in centimeters per second is the radius changing when the radius is 3 centimeters?
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If the multiplicity of a system increases from 10 to 1000, by what factor is the entropy of the system multiplied?
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Kevin, who has mass 50 kilograms, is standing motionless on a skating rink when he throws the 10-kilogram rock he is holding at a velocity of 15 meters per second at an angle 45 degrees above the horizontal. What is his speed, to the nearest meter per second, after he does this?
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What constellation contains the celestial South Pole?
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Rank the following three planets in increasing order of equatorial magnetic field strength: 1) Mars; 2) Jupiter; 3) Earth.
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What is the IUPAC name for the compound with the chemical formula K₂[Cu(CN)₄]?
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Nitric oxide contains 10 electrons in bonding orbitals and 5 electrons in antibonding orbitals. What is its bond order?
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When viewed in cross-section, in which plant organ would you find a star-shaped zone of xylem? W) Monocot stem X) Gymnosperm stem Y) Dicot root Z) Dicot stem
W: W) Monocot stem
X: X) Gymnosperm stem
Y: Y) Dicot root
Z: Z) Dicot stem
Answer: Y) Y) Dicot root
Identify all of the following three locations in a dNTP that, when radioactively labeled, will be retained in the final DNA molecule: 1) Alpha phosphate 2) Beta phosphate 3) Gamma phosphate
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