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When 650 adults are randomly selected, find the probability that 84 or more of them are lefthanded. Does the result of 84 lefthanded adults appear to be unusually high? The volume of air inside a bottle affects its resonant frequency. a. What are the dependent and independent variables? b. Suggest one quantity to be controlled. c. How would you produce sounds of... The effective rate constant for a gaseous reaction that has a LindemannHinshelwood mechanism is 2.50 10 4 s 1 at 1.30 kPa and 2.10 10 5 s 1 at 12 Pa. Calculate the rate constant for the activation... Ayurveda is a traditional medical system commonly used in India. Listed below are the lead concentrations (in g/g) measured in different Ayurveda medicines (manufactured in the United States). (Data... Calculate the change in entropy when 15 g of carbon dioxide gas is allowed to expand from 1.0dm 3 to 3.0dm 3 at 300K. Consider a system of particles uniformly distributed in space, with a constant particle number density n 0 , and characterized by a velocity distribution function f(v) such that where K 0 is a... The rotational constants B 0 have been determined for three isotopic derivatives of chloroacetylene: Assume that the carbon isotope is 12 C in all cases. Calculate the three bond distances in... Compute the transition dipole and oscillator strength for the following hydrogen atom transitions 1s 3p 0 and 1s 4p 0 . There is a 0.9968 probability that a randomly selected 50-year-old female will live through the year. A life insurance company charges $226 for insuring that the female will live through the year. If... Consider the graph of the normal distribution in Figure 5.12, which gives relative frequencies in the distribution of mens heights. The distribution has a mean of 69.6 inches and a standard deviation... Find the difference between the ground- and first excited-state translational energies of a helium atom in a 1 mm 3 cubic box. Compare this to room temperature energy k B T at 300 K. An RLC circuit has a resistance of 255 , an inductance of 146 mH, and a capacitance of 877 nF. (a) What is the resonant frequency of this circuit? (b) If this circuit is connected to a sinusoidal... The diagram shows a simplified household circuit. Resistor r 1 = 240.0 represents a lightbulb; resistor r 2 = 12.0 represents a hair dryer. The resistors r = 0.50 (each) represent the resistance... The scatterplot in Figure 7.18 depicts paired data values consisting of the weight (in grams) and year of manufacture for each of 72 pennies. a. Considering the complete collection of data, does... Translate the azimuth convention into the quadrant convention, or vice versa. a) N12E b) 298 c) N86W d) N55E e) 126 f) N37W g) 233 h) 270 i) 083 j) N3W Growth hormone, or GH, is used medically to spur growth in children who are unusually short because they have a GH deficiency. However, it is useless for a short but otherwise normal 25-year-old to... In a mitochondrion, where are the electron transport systems and enzymes required for ATP formation located? What kinds of bonds often control the shape (or tertiary form) of large molecules such as proteins? a. Hydrogen d. Inert b. Ionic e. Single c. Covalent Match each type of molecule with its description. || chain of amino acids energy carrier glycerol, fatty acids, phosphate chain of nucleotides one or more sugar units a. carbohydrate b. phospholipid... _______carry out most membrane functions. a. Proteins c. Nucleic acids b. Phospholipids d. Hormones Cell membranes consist mainly of a _______. a. Carbohydrate bilayer and proteins b. Protein bilayer and phospholipids c. Phospholipid bilayer and proteins Humans are________ (animals with backbones); like other primates, they also are________. You are a living organism. Which characteristics of life do you exhibit? Enzymes _______. a. Enhance reaction rates b. Are affected by pH c. Act on specific substrates d. All of the above The passive movement of a solute through a membrane protein down its concentration gradient is an example of _______. a. Osmosis b. Active transport c. Endocytosis d. Diffusion A carbon atom can form up to ________ bonds with other atoms. a. Four b. Six c. Eight d. Sixteen A related set of hypotheses that collectively explain some aspect of the natural world makes up a scientific ________ . a. Prediction b. Test c. Theory d. Authority e. Observation Which of the following is not a feature of a scientific theory? a. It begins as a hypothesis. b. It eventually is accepted as absolute truth. c. It requires critical thinking. d. It is not accepted... Muscle fatigue _______. a. Occurs when ATP runs out b. May be caused by oxygen debt c. Is a state in which a muscle can no longer contract d. All of the above Skeletal muscle contraction requires _______. a. Calcium ions b. ATP c. Arrival of a nerve impulse d. All of the above The number 6 has four divisorsnamely, 1, 2, 3, and 6. List all numbers less than 20 that have exactly four divisors. The volume of a typical neuron is about 3 10 -8 cm 3 . Write each of the numbers in Problems 1922 in fixed-point notation. Plot the expected steady state pattern (as a function of distance from the crest) of discharge of regolith on a convex hillslope in a climate in which the production rate of regolith is 20 mm/yr.... The rotational constants for HF are (a) Find the initial J value and the frequency for the most intense rotational transition taking place in the ground vibrational state at room temperature. (b)... Discuss how rivers might differ if the fluid being transported were of a different density or viscosity or both. And lest you think this silly, we are learning about a landscape on Titan that appears... Discuss how a bedrock river should respond to glacial-interglacial fluctuations in base level of order 120 m. What legacy of the glacial sea level low stand might be seen in the present profile or... From unit-cell parameters in figures in this chapter, calculate the following shortest distances: (a) NaCl and NaNa in NaCl, (b) NiNi in NiAs, (c) CaF in CaF 2 , (d) CC in diamond, (e) TiTi in TiO 2... Air is flowing steadily through a horizontal tube at a constant temperature of $32^{\circ} \mathrm{C}$ and a mass flow rate of $1 \mathrm{~kg} / \mathrm{s}$. At one point upstream where the tube... The "yield stress" for carbon steel is 35,000 psi, and the "working stress" is one-half of this value. What schedule number would you recommend for a pipe carrying ethylene at a pressure of $2500... A tank that is vented to the atmosphere contains a liquid with a density of $0.9 \mathrm{~g} / \mathrm{cm}^{3}$. A dip tube inserted into the top of the tank extends to a point $1 \mathrm{ft}$ from... A mercury manometer is used to measure the pressure drop across an orifice that is mounted in a vertical pipe. A liquid with a density of $0.87 \mathrm{~g} / \mathrm{cm}^{3}$ is flowing upward... A gas well contains hydrocarbon gases with an average molecular weight of 24 , which can be assumed to be an ideal gas with a specific heat ratio of 1.3. The pressure and temperature at the top of... Two identical tanks are $3 \mathrm{ft}$ in diameter and $3 \mathrm{ft}$ high, and they are both vented to the atmosphere. The top of tank B is level with the bottom of tank A, and they are connected... How many truckloads of trucks hauling an average volume of 6 LCY (4.6 LCM) would be required to haul 1 million CCY (764 600 CCM) of the soil of Problem 7 to a dam site? A soil weighs 2500 lb/cu yd (1483 kg/m 3 ) loose, 3100 lb/cu yd (1839 kg/m 3 ) in its natural state, and 3650 lb/cu yd (2106 kg/m 3 ) compacted. Find this soil s load factor and shrinkage factor. Using Table 21, how many working minutes per hour would you expect to achieve on a project whose job conditions and management conditions are both rated poor? Table 2-1: Use the profile and mass diagram of Figure 26 to find the following values. a. The total volume of (1) cut, (2) fill, (3) waste, and (4) borrow . b. The average length of haul for section 3. Figure... Write a computer program to determine the height and base width (feet or meters) of the triangular spoil bank that will result from a rectangular trench excavation. Input should include the ditch... Identify the reagents necessary to accomplish each of the transformations shown below. If you are having trouble, the reagents for these transformations appear on page 444, but you should first try... Identify the reagents that you would use to accomplish each of the following transformations: a. b. c. d. e. f. -Br OH Draw a mechanism and predict the major product for each reaction. a. b. c. d. e. f. ? 1) LAH H. 2) H20 Identify the reagents you would use to achieve the following transformations: a. b. Br Br The following triene reacts with excess maleic anhydride to produce a compound with molecular formula C 14 H 12 O 6 . Draw the structure of this product (ignoring stereochemistry). Maleic anhydride... The temperature of 1.75 moles of an ideal gas increases from 10.2C to 48.6C as the gas is compressed adiabatically. Calculate q, w, U, and H for this process assuming that C V ,m = 3/2 R. Draw the mechanism for each of the following reactions: a. b. c. NaOMe CI NaOEt. Br In the experiment shown in Figure 2.4b, the weight drops in a very short time. How will the temperature of the water change with time? Figure 2.4b Electrical generator Mass Heating - coil (b) Identify the reagents necessary to accomplish each of the transformations below: (a) (b) Why is there an upper limit to the photon energy that can be observed in the emission spectrum of the hydrogen atom? Propose an efficient synthesis for the following transformation. Draw the structure of the product with molecular formula C 10 H 10 O that is obtained when the compound below is heated with aqueous acid. CN CN C10H100 Heat Propose an efficient synthesis for each of the following transformations: (a) (b) Why is the probability of finding the harmonic oscillator at its maximum extension or compression larger than that for finding it at its rest position? A gas-phase 1 H 127 I molecule, with a bond length of 160.92 pm, rotates in three dimensional space. a. Calculate the zero point energy associated with this rotation. b. What is the smallest quantum... Derive the ground-state term symbols for the following configurations: a. d 5 b. f 3 c. p 4 The electron affinities of He, Be, and Ne are negative, meaning that the negative ion is less stable than the neutral atom. Explain why this is so for these three elements. Calculate the mean value of the radius r at which you would find the electron if the H atom wave function is 210 (r, , ). Propose an efficient synthesis for each of the following compounds using the acetoacetic ester synthesis. (a) (b) (c) (d) Show by carrying out the appropriate integration that the total energy eigenfunctions for the harmonic oscillator 0 (x) ( /) 1/4 e -(1/2)ax2 and 2 (x) ( /4) 1/4 (2x - 1) e -(1/2)ax2 are orthogonal... Fill in the missing step in the derivation that led to the calculation of the spectral line shape in Figure 19.24. Starting from and neglecting the first term in the parentheses, show that Figure... Evaluate the vibrational partition function for CFCl 3 at 298 K, where the vibrational frequencies are (with degeneracy in parentheses) 1081, 847 (2), 535, 394 (2), 350., and 241(2) cm 1 . The Grotrian diagram in Figure 22.7 shows a number of allowed electronic transitions for He. Which of the following transitions shows multiple spectral peaks due to a splitting of terms into levels?... The half-life of 238 U is 4.5 10 9 years. How many disintegrations occur in 1 minute for a 10.0-mg sample of this element? Use the VSEPR method to predict the structures of the following: a. PCl 5 b. SO 2 c. XeF 2 d. XeF 6 Determine the maximum magnitude P of the loads the beam can support if the average shear stress in each pin is not to exceed 80 MPa. All pins are in double shear, and each has a diameter of 18 mm. 6P... One loss mechanism for ozone in the atmosphere is the reaction with the HO2 radical: HO 2 · (g) + O 3 (g) OH · (g) + 2O 2 (g) Using the following information, determine the rate law... The rectangular plate is deformed into the shape shown by the dashed lines. Determine the average normal strain along diagonal BD, and the average shear strain at corner B relative to the x, y axes.... The beam supports the triangular distributed load shown. Determine the resultant internal loadings on the cross section at point C. Assume the reactions at the supports A and B are vertical. 800... Determine the largest load P that can be applied to the frame without causing either the average normal stress or the average shear stress at section aa to exceed Ï = 150 MPa and Ï = 60... The rigid bar is supported by the pin-connected rod CB that has a cross-sectional area of 14 mm 2 and is made from 6061-T6 aluminum. Determine the vertical deflection of the bar at D when the... The 2014-T6 aluminium rod has a diameter of 30 mm and supports the load shown. Determine the displacement of end A with respect to end E. Neglect the size of the couplings. 8 kN 2 kN 6 kN 4 kNY -2m-... The 3-in.-diameter shaft is made of an elastic perfectly plastic material as shown. Determine the radius of its elastic core if it is subjected to a torque of T = 18 kip ft. If the shaft is 3 ft... Express the internal shear and moment in the cantilevered beam as a function of x and then draw the shear and moment diagrams. 300 Ib 200 lb/ft 6 ft Draw the shear and moment diagrams for the beam and determine the shear and moment in the beam as functions of x, where 4 ft < x < 10 ft. 150 Ib/ft 200 lb-ft 200 Ib-ft B- 4 ft ft- 6 ft 4 ft The beam is subjected to a moment of 15 kip ft. Determine the percentage of this moment that is resisted by the web D of the beam. 1 in. 5 in. 8 in. M = 15 kip-ft- 1 in. 1 in. 3 in The beam has a rectangular cross section with b = 4 in. Determine the largest maximum intensity w 0 of the triangular distributed load that can be supported if the allowable bending stress is Ï... The Douglas Fir beam is reinforced with A-992 steel straps at its sides. Determine the maximum stress in the wood and steel if the beam is subjected to a moment of M z = 80 kN · m. Sketch the... A wooden beam has a square cross section as shown. Determine which orientation of the beam provides the greatest strength at resisting the moment M. What is the difference in the resulting maximum... The composite beam consists of a wood core and two plates of steel. If the allowable bending stress for the wood is (Ï allow ) w = 20 MPa, and for the steel (Ï allow ) st = 130 MPa,... Determine the shape factor for the wide-flange beam. 15 mm 20 mm 200 mm M. 15 mm 200 mm Determine the shear stress at points B and C on the web of the beam located at section aa. 8000 lb 150 Ib/ft B. 4 ft -4 ft - 1.5 ftT1.5 ft Determine the location e of the shear center, point O, for the thin-walled member. The member segments have the same thickness t. -- IT The steel water pipe has an inner diameter of 12 in. and a wall thickness of 0.25 in. If the valve A is opened and the flowing water has a pressure of 250 psi as it passes point B, determine the... Determine the normal stress developed at points A and B. Neglect the weight of the block. 6 kip 3 in. 12 kip 6 in.: D. B. A bar having a square cross section of 30 mm by 30 mm is 2 m long and is held upward. If it has a mass of 5 kg/m, determine the largest angle u, measured from the vertical, at which it can be... Determine the equivalent state of stress on an element at the point which represents (a) the principal stresses and (b) the maximum in-plane shear stress and the associated average normal stress.... Determine the equivalent state of stress on an element at the same point which represents (a) the principal stress, and (b) the maximum in-plane shear stress and the associated average normal stress.... The wood beam is subjected to a load of 12 kN. If grains of wood in the beam at point A make an angle of 25° with the horizontal as shown, determine the normal and shear stress that act... Determine the equivalent state of stress if an element is oriented 60° clockwise from the element shown. 65 ksi The box beam is subjected to the 26-kN force that is applied at the center of its width, 75 mm from each side. Determine the principal stresses at point A and show the results in an element located... The bolt is fixed to its support at C. If a force of 18 lb is applied to the wrench to tighten it, determine the principal stresses and the absolute maximum shear stress in the bolt shank at point A....
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