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If pp annihilation at rest proceeds via S-states, explain why the reaction pp 0 0 is forbidden as a strong or electromagnetic interaction. The charmed particle decays, D + (1869) e + + anything, D 0 (1869) e + + anything, + c (2285) e + + anything, are usually assumed to result from the charmed quark decay c s + e + + e discussed... Use the quark distributions of Figure 8.7 to make a rough estimate of the fraction of the proton momentum in a high-momentum frame that is carried by its quark and antiquark constituents. To what... The K + and its excited states with masses below 1.5 GeV/c 2 are shown in Figure 3.12. Identify these mesons with states 2S + 1 L J of the appropriate quarkanti quark system, specifying the value of... Show that the impulse on a baseball that is hit with 100 N of force in a time of 0.5 s is 50 N.s. Impulse = change in momentum; Ft = ????mv Show that 2.4 J of work is done when a force of 2.0 N moves a book 1.2 m. (1 N m = 1 J) Show that when a 3.0-kg book is lifted 2.0 m, its increase in gravitational potential energy is 60 J. Show that the kinetic energy of a 1.0-kg book tossed across the room at a speed of 3.0 m/s is 4.5 J. (1 J is equivalent to 1 kg(m/s) 2 .) Jeannie Beanie (mass 40 kg), standing on slippery ice, catches her leaping dog, Daisy (mass 20 kg), who leapt into her arms after running across an adjacent field at 6 m/s. Use the conservation of... Choose your favorite local mountain. Estimate how much energy it takes to hike to the top of the mountain (ignoring all the local ups and downs of a typical trail). How does your result compare to a... Estimate the kinetic energy of the ocean liner Queen Mary 2, with mass (displacement) 76000 tons, moving at a cruising speed of 26 knots. Compare with the change in potential energy of the Queen Mary... Estimate the potential energy of the international space station (mass 370000 kg) relative to Earths surface when in orbit at a height of 350 km. Compute the velocity of the space station in a... Consider an idealized cylinder of cross-sectional area A moving along its axis through an idealized diffuse gas of air molecules with vanishing initial velocity. Assume that the air molecules are... How much energy can you store on a parallel plate capacitor with d = 1 m, A = 10 cm 2 , and = 100 0 ,assuming that the breakdown field of the dielectric is the same as for air? An electric motor operates at 1000 rpm with an average torque of = 0.1Nm. What is its power output? If it is running on 1.2A of current, estimate the back-EMF from the rotor. Explain why the integral that appears in eq. is independent of the choice of surface S .[make use of eq. k dS B dS (V x E) = dt dS B A start-up company is marketing steel ice cubes to be used in place of ordinary ice cubes. How much would a liter of water, initially at 20 C, be cooled by the addition of 10 cubes of steel, each... A new solar thermal plant being constructed in Australia will collect solar energy and store it as thermal energy, which will then be converted to electrical energy. The plant will store some of the... Nuclear forces are so strong that they keep protons and neutrons in a spherical region a few femtometers in radius (1 fm = 10 15 m). To get a crude idea of the energy scales involved in nuclear... A blue super giant star may have a surface temperature as high as 50000 K. Estimate the wavelength at which it emits maximum power. Why does the star appear blue? Find the enthalpy of reaction for the two pathways of decomposition of TNT. Acetylene (used in welding torches) C 2 H 2 , sucrose(cane sugar) C 12 H 22 O 11 , and caffeine C 8 H 10 O 2 N 4 , are all popular energy sources. Their heats of combustion are 310.6 kcal/mol, 1348.2... Thermite is a mixture of powdered metallic aluminum and iron oxide (usually Fe 2 O 3 ). Although stable at room temperature, the reaction 2Al + Fe 2 O 3 Al 2 O 3 + 2 Fe proceeds quickly when thermite... Show that roasting lead (2PbS + 3O 2 ? 2 PbO +2 SO 2 ) is an exothermic reaction and compute the free energy of this reaction under standard conditions. See Table for data. Compound AG (kJ/mol)... Assume that an SI engine has the following parameters : displacement (V 1 V 2 ): 2.4 L; compression ratio 9.5:1; air to fuel mass ratio 15:1; heating value of fuel 44MJ/kg, pressure at start of... The energy levels of the one-dimensional harmonic oscillator are given by E n = (n + 1/2) with n = 0, 1, 2, . . . . Suppose two spin-1/2 fermions are trapped in a one-dimensional oscillator... The radius of a nucleon is about R N = 0.9 fm. Compute the volume of a nucleus with a moderately large value of A in the liquid drop model (i.e. using the SEMF) and show that roughly 2/3 of the... 235 U can decay by emitting a neon nucleus. How many such decays occur per second per mole of 235 U? Radon gas 222 86 Rn is a serious environmental hazard(see 20). It is a decay product of 238 92 U, which is a relatively common constituent of rock. 222 86 Rn undergoes-decay to 218 84 Po. When 222 86... A beam of thermal neutrons with current? is incident on a uniform (thin) target of thickness 1 cm, consisting of 20% 235 U and 80% 238 U. Table 18.3 ? ? and Problem 18.1. What is the fission rate?... Show that the peak of the black body spectrum as a function of ? is given by eq. (22.14) kg T Wmax = 2.82 Consider a flat-plate collector covered by a single pane of glass exposed to perpendicular insolation at 1000 W/m 2 . The collector operates at a net efficiency of 35% at a temperature T b 65 C.... Estimate the maximum possible collection efficiency max collection for a germanium solar cell (E gap 0.66 eV). Compute the maximum energy content of the ethanol produced from corn farmed at 10 t/ha y, assuming that the corn is 70% starch composed of polysaccharides (amylose and amylopectin) built from glucose... Wind frequency data obtained at a height of 10 meters at a particular location is summarized by a Weibull distribution with = 9 m/s and k = 1.3. The land use is best characterized as rough pasture.... Consider a deep-water wave with amplitude a = 1 m and period 12 s. Compute the energy density and power. When the wave moves into shallow water, what is the height and energy density of the wave at 2... Use blade-element theory to compute the correction to the axial-momentum theory expression for the power (30.7) To first order in c d /c l for an optimized blade. First, recompute f T and f N... Consider building a tidal barrage along a straight section of beach in California. Assume that the average tidal range is 3 m, with two high tides a day. Assume that the tidal basin is 20 m wide and... A tsunami is a very long-wavelength wave produced by a sudden movement in the sea floor over a distance of hundreds of kilometers. The wavelengths in a tsunami are generally much greater than ocean... An electric space heater dissipates 1320 W of power via electromagnetic radiation and convection when connected to 120 V. When current is unknown, power can be expressed as P = V 2 /R . Use this... A friend says that sound travels faster in warm air than in cooler air. Do you agree or disagree? Physics instructor Peter Hopkinson delights in bringing physics into social situations. When dining out with friends, he produces resonance in an empty wine glass by rubbing his wetted fingers on its... Quantum mechanics is one of the most daunting of all areas in physics. To students encountering this subject for the first time at the introductory level, quantum mechanics can seem mysterious, even... How much unpolarized light does an ideal Polaroid filter transmit? Which electrons are most responsible for the properties of an atom? How might you distinguish a sodium-vapor streetlight from a mercury-vapor streetlight? If matter is made of atoms, and atoms are made of subatomic particles, what comes together to create subatomic particles? Where might you find such information? Why is the rusting of iron considered to be a chemical change? Which element within a compound is given first in the compounds name? A driver states that she was doing 80 when stopped by the police. Is that a clear statement? Would this be interpreted differently in England than it would be in the United States? Explain. In shooting a free throw in basketball, what is the primary advantage that a high, arching shot has over one with a flatter trajectory? Explain. A 4-kg block is acted upon by three horizontal forces as shown in the diagram. a. What is the net horizontal force acting on the block? b. What is the horizontal acceleration of the block? 10 N 5 N... At a given instant in time, a 4-kg rock that has been dropped from a high cliff experiences a force of air resistance of 15 N. What are the magnitude and direction of the acceleration of the rock?... At a given instant in time, a 5-kg rock is observed to be falling with an acceleration of 7.0 m/s 2 . What is the magnitude of the force of air resistance acting upon the rock at this instant? A 0.5-kg book rests on a table. A downward force of 6 N is exerted on the top of the book by a hand pushing down on the book. a. What is the magnitude of the gravitational force acting upon the book?... Assume that a passenger in a rollover accident must turn through a radius of 3.0 m to remain in the seat of the vehicle. Assume also that the vehicle makes a complete turn in 1 second. a. Using the... Suppose that the physics instructor pictured in figure 6.15 gives the bowling ball a push as she releases it. Will the ball return to the same point or will her chin be in danger? Explain. A force of 50 N is used to drag a crate 4 m across a floor. The force is directed at an angle upward from the crate so that the vertical component of the force is 30 N and the horizontal component is... What kind of weather does a continental tropical air mass bring? An underground mass of salt may form a dome trapping a petroleum reservoir. Compute the gravitational anomaly (deviation of gravitational acceleration) produced by an underground salt mass, where for... Compare the energy density of oil and geothermal fluid at 250 C pumped from oil/geothermal wells at a rate of 30 L/s. To make a fair comparison, assume that the oil is transformed into useful... According to the US EIA, 1350 Mt(CO 2 ) were emitted from combustion of coal and 530 Mt(CO 2 ) we re emitted from combustion of natural gas for electricity production in 2015. Using the data in... Confirm explicitly that the work (37.2) done in isothermal compression of a CAES system with volume V, and low, high, and ambient atmospheric pressures p L , p H , p 0 is equivalent to the energy... Verify the computations in Example 37.2 describing the McIntosh CAES plant. In particular, use eq. (37.2) to compute the energy stored through isothermal compression; verify that 1.4 TJ of work would... In a lithium-iodine (LiI) battery, a solid lithium anode is surrounded by a polymer impregnated with iodine. The net reaction, Li + I 2 LiI, has a standard reaction free energy of G 0 = 266.9 kJ/mol... A load consists of a large number N of identical resistors R (e.g. incandescent lights, toasters,. . . ) in parallel.Suppose they are powered by an AC generator with RMS voltage V. Compare the line... Compute the time for the oceanic mixed layer (350 Mkm 2 200 m) to warm by 3.2 K, using 50% of the energy coming from a change in radiative forcing of 3.7 W/m 2 . Advanced version: assume that... Estimate the contribution to global sea level rise over a century if Greenlands glaciers continue to melt at a rate of 290 Gt/y. In 13.3.5 we specified a realistic Rankine cycle working between T + = 600 C and T = 36 C. We found its efficiency to be 38%.What is its 2nd law efficiency? A three-phase generator delivers voltages V A (t) = V 0 cost, V B (t) = V 0 cos(t + 2/3), and V C (t) = V 0 cos (t 2/3). First, assume that all three phases are connected to identical, purely... Fluorescent light bulbs have significant impedance. Measurements on a compact fluorescent bulb with luminosity equivalent to a 40 W incandescent indicate that it consumes 9 W real power. Measurements... Based upon the descriptions provided in table 1.2, which subfields of physics are involved in explaining why an ice cube melts? Which subfields are involved in explaining how an airplane flies?... A uniform metal wire is bent into the shape of an L. Will the center of gravity for the wire lie on the wire itself? Explain. The rotational velocity of a spinning disk decreases from 6 rev/s to 3 rev/s in a time of 12 s. What is the rotational acceleration of the disk? A torque of 60 Nm producing a counterclockwise rotation is applied to a wheel about its axle. A frictional torque of 10 Nm acts at the axle. a. What is the net torque about the axle of the wheel? b.... Two 0.2-kg masses are located at either end of a 1-m long, very light and rigid rod as in the diagram. What is the rotational inertia of this system about an axis through the center of the rod? Axis... A 4-m long plank with a weight of 80 N is placed on a dock with 1 m of its length extended over the water, as in the diagram. The plank is uniform in density so that the center of gravity of the... Is it possible for a 100-lb woman to exert a greater pressure on the ground than a 250-lb man? Explain. The same force is applied to two cylinders that contain air. One has a piston with a large area, and the other has a piston with a small area. In which cylinder will the pressure be greater? Explain Why are bicycle tires often inflated to a higher pressure than automobile tires, even though the automobile tires must support a much larger weight? Explain. The fluid in a hydraulic system pushes against two pistons, one with a large area and the other with a small area. a. Which piston experiences the greater force due to fluid pressure acting on it?... If the output piston in a hydraulic pump exerts a greater force than one applied to the input piston, is the pressure at the output piston also larger than at the input piston? Explain. When a mercury barometer is used to measure atmospheric pressure, does the closed end of the tube above the mercury column usually contain air? Explain. Could we use water instead of mercury to make a barometer? What advantages and disadvantages would be associated with the use of water? Explain. If you climbed a mountain carrying a mercury barometer, would the level of the mercury column in the glass tube of the barometer increase or decrease (compared to the mercury reservoir) as you climb... If an object has a smaller density than water, will the object stay fully submerged, partly submerged, or rise completely out of the water when it is released underwater? Explain. A 250-lb man supports all of his weight on a show shoe with an area of 200 in 2 . What pressure is exerted on the snow (in pounds per square inch)? The pressure of a gas contained in a cylinder with a movable piston is 450 Pa (450 N/m 2 ). The area of the piston is 0.2 m2. What is the magnitude of the force exerted on the piston by the gas? In a hydraulic system, a force of 400 N is exerted on a piston with an area of 0.001m 2 . The load-bearing piston in the system has an area of 0.2m 2 . a. What is the pressure in the hydraulic fluid?... The load-bearing piston in a certain hydraulic system has an area 50 times as large as the input piston. If the larger piston supports a load of 6000 N, how large a force must be applied to the input... A block of wood of uniform density floats so that exactly half of its volume is underwater. The density of water is 1000 kg/m 3 . What is the density of the block? A certain boat displaces a volume of 4.5 m 3 of water. (The density of water is 1000 kg/m 3 .) a. What is the mass of the water displaced by the boat? b. What is the buoyant force acting on the boat? Water emerges from a faucet at a speed of 1.5 m/s. After falling a short distance, its speed increases to 3 m/s as a result of the gravitational acceleration. By what number would you multiply the... Water has a density of 1000 kg/m 3 . The depth of a swimming pool at the deep end is about 3 m. a. What is the volume of a column of water 3 m deep and 0.5m 2 in cross-sectional area? b. What is the... An object has a temperature of 45C. What is its temperature in degrees Fahrenheit? The temperature on a winter day is 14F. What is the temperature in degrees Celsius? The temperature in a residence-hall room is 24C. What is the temperature of the room on the absolute (Kelvin) temperature scale? The temperature on a warm summer day is 95F. What is this temperature a. In degrees Celsius? b. On the absolute (Kelvin) scale? The temperature of a beaker of water is 318.2 K. What is this temperature a. In degrees Celsius? b. In degrees Fahrenheit? How much heat is required to raise the temperature of 70 g of water from 20C to 80C?
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