The spectrum of the sodium atom is detected in the light from a distant galaxy. a. If the 590.0-nm line is redshifted to 658.5 nm, at what speed is the galaxy receding from the earth? b. Use the Hubble law to calculate the distance of the galaxy from the earth.
> In Section 40.5 it is shown that for the ground level of a harmonic oscillator, ∆x ∆px = ħ/2. Do a similar analysis for an excited level that has quantum number n. How does the uncertainty product ∆x ∆px depend on n?
> While undergoing a transition from the n = 1 to the n = 2 energy level, a harmonic oscillator absorbs a photon of wavelength 6.50 µm. What is the wavelength of the absorbed photon when this oscillator undergoes a transition a. from the n = 2 to the n =
> The groundstate energy of a harmonic oscillator is 5.60 eV. If the oscillator undergoes a transition from its n = 3 to n = 2 level by emitting a photon, what is the wavelength of the photon?
> A harmonic oscillator absorbs a photon of wavelength 6.35 µm when it undergoes a transition from the ground state to the first excited state. What is the groundstate energy, in electron volts, of the oscillator?
> Chemists use infrared absorption spectra to identify chemicals in a sample. In one sample, a chemist finds that light of wavelength 5.8 µm is absorbed when a molecule makes a transition from its ground harmonic oscillator level to its first excited level
> Show that ψ(x) given by Eq. (40.47) is a solution to Eq. (40.44) with energy E0 = ħω/2. From Eq. (40.47) From Eq. (40.44)
> A wooden block with mass 0.250 kg is oscillating on the end of a spring that has force constant 110 N/m. Calculate the groundlevel energy and the energy separation between adjacent levels. Express your results in joules and in electron volts. Are quantu
> The wave function shown in Fig. 40.20 is nonzero for both x L. Does this mean that the particle splits into two parts when it strikes the barrier, with one part tunneling through the barrier and the other part bouncing off the barrier? Explain. From Fi
> A proton with initial kinetic energy 50.0 eV encounters a barrier of height 70.0 eV. What is the width of the barrier if the probability of tunneling is 8.0 * 10-3? How does this compare with the barrier width for an electron with the same energy tunneli
> An electron is moving past the square barrier shown in Fig. 40.19, but the energy of the electron is greater than the barrier height. If E = 2U0, what is the ratio of the de Broglie wavelength of the electron in the region x > L to the wavelength for
> An electron with initial kinetic energy 5.0 eV encounters a barrier with height U0 and width 0.60 nm. What is the transmission coefficient if a. U0 = 7.0 eV; b. U0 = 9.0 eV; c. U0 = 13.0 eV?
> An electron with initial kinetic energy 6.0 eV encounters a barrier with height 11.0 eV. What is the probability of tunneling if the width of the barrier is a. 0.80 nm and b. 0.40 nm?
> In a simple model for a radioactive nucleus, an alpha particle (m = 6.64 * 10-27 kg) is trapped by a square barrier that has width 2.0 fm and height 30.0 MeV. a. What is the tunneling probability when the alpha particle encounters the barrier if its kin
> a. An electron with initial kinetic energy 32 eV encounters a square barrier with height 41 eV and width 0.25 nm. What is the probability that the electron will tunnel through the barrier? b. A proton with the same kinetic energy encounters the same bar
> An electron is bound in a square well that has a depth equal to six times the groundlevel energy E1-IDW of an infinite well of the same width. The longestwavelength photon that is absorbed by this electron has a wavelength of 582 nm. Determine the widt
> A proton is bound in a square well of width 4.0 fm = 4.0 * 10-15 m. The depth of the well is six times the groundlevel energy E1-IDW of the corresponding infinite well. If the proton makes a transition from the level with energy E1 to the level with ene
> An electron is in the ground state of a square well of width L = 4.00 * 10-10 m. The depth of the well is six times the groundstate energy of an electron in an infinite well of the same width. What is the kinetic energy of this electron after it has abs
> An electron is bound in a square well of width 1.50 nm and depth U0 = 6E1-IDW. If the electron is initially in the ground level and absorbs a photon, what maximum wavelength can the photon have and still liberate the electron from the well?
> Qualitatively, how would you expect the probability for a particle to tunnel through a potential barrier to depend on the height of the barrier? Explain.
> An electron is moving past the square well shown in Fig. 40.13. The electron has energy E = 3U0. What is the ratio of the de Broglie wavelength of the electron in the region x > L to the wavelength for 0 < x < L?
> An electron is bound in a square well of depth U0 = 6E1-IDW. What is the width of the well if its groundstate energy is 2.00 eV?
> When an electron in a onedimensional box makes a transition from the n = 1 energy level to the n = 2 level, it absorbs a photon of wavelength 426 nm. What is the wavelength of that photon when the electron undergoes a transition a. from the n = 2 to th
> An electron is in a box of width 3.0 * 10-10 m. What are the de Broglie wavelength and the magnitude of the momentum of the electron if it is in a. the n = 1 level; b. the n = 2 level; c. the n = 3 level? In each case how does the wavelength compare
> a. Find the excitation energy from the ground level to the third excited level for an electron confined to a box of width 0.360 nm. b. The electron makes a transition from the n = 1 to n = 4 level by absorbing a photon. Calculate the wavelength of this
> Repeat Exercise 40.16 for the particle in the first excited level.
> Recall that |ψ|2dx is the probability of finding the particle that has normalized wave function ψ(x) in the interval x to x + dx. Consider a particle in a box with rigid walls at x = 0 and x = L. Let the particle be in the ground level and use ψn as give
> Consider a particle moving in one dimension, which we shall call the xaxis. a. What does it mean for the wave function of this particle to be normalized? b. Is the wave function ψ(x)= eax , where a is a positive real number, normalized? Could this be
> An electron in a onedimensional box has groundstate energy 2.00 eV. What is the wavelength of the photon absorbed when the electron makes a transition to the second excited state?
> A certain atom requires 3.0 eV of energy to excite an electron from the ground level to the first excited level. Model the atom as an electron in a box and find the width L of the box.
> Figure 40.17 shows the scanning tunneling microscope image of 48 iron atoms placed on a copper surface, the pattern indicating the density of electrons on the copper surface. What can you infer about the potential-energy function inside the circle of iro
> A student remarks that the relationship of ray optics to the more general wave picture is analogous to the relationship of Newtonian mechanics, with well-defined particle trajectories, to quantum mechanics. Comment on this remark.
> When a hydrogen atom undergoes a transition from the n = 2 to the n = 1 level, a photon with λ = 122 nm is emitted. a. If the atom is modeled as an electron in a onedimensional box, what is the width of the box in order for the n = 2 to n = 1 transitio
> Find the width L of a onedimensional box for which the groundstate energy of an electron in the box equals the absolute value of the ground state of a hydrogen atom.
> A proton is in a box of width L. What must the width of the box be for the groundlevel energy to be 5.0 MeV, a typical value for the energy with which the particles in a nucleus are bound? Compare your result to the size of a nucleus—that is, on the ord
> a. Find the lowest energy level for a particle in a box if the particle is a billiard ball (m = 0.20 kg) and the box has a width of 1.3 m, the size of a billiard table. (Assume that the billiard ball slides without friction rather than rolls; that is, ig
> Deuterons in a cyclotron travel in a circle with radius 32.0 cm just before emerging from the dees. The frequency of the applied alternating voltage is 9.00 MHz. Find a. the magnetic field and b. the kinetic energy and speed of the deuterons upon emerg
> An electron with a total energy of 30.0 GeV collides with a stationary positron. a. What is the available energy? b. If the electron and positron are accelerated in a collider, what total energy corresponds to the same available energy as in part (a)?
> The starship Enterprise, of television and movie fame, is powered by combining matter and antimatter. If the entire 400-kg antimatter fuel supply of the Enterprise combines with matter, how much energy is released? How does this compare to the U.S. yearl
> Estimate the range of the force mediated by an ω0 meson that has mass 783 MeV/c2.
> For the nuclear reaction given in Eq. (44.2) assume that the initial kinetic energy and momentum of the reacting particles are negligible. Calculate the speed of the α particle immediately after it leaves the reaction region.
> A proton and an antiproton annihilate, producing two photons. Find the energy, frequency, and wavelength of each photon a. if the p and p are initially at rest and b. if the p and p collide head-on, each with an initial kinetic energy of 620 MeV.
> In classical (Newtonian) mechanics, the total energy E of a particle can never be less than the potential energy U because the kinetic energy K cannot be negative. Yet in barrier tunneling (see Section 40.4) a particle passes through regions where E is l
> Calculate the reaction energy Q (in MeV) for the nucleosynthesis reaction 6 12
> The 2.728-K blackbody radiation has its peak wavelength at 1.062 mm. What was the peak wavelength at t = 700,000 y when the temperature was 3000 K?
> Calculate the energy (in MeV) released in the triple alpha process 3 4He → 12C.
> Calculate the reaction energy Q (in MeV) for the reaction e- + p → n + ve. Is this reaction endoergic or exoergic?
> The definition of the redshift z is given in Example 44.8. a. Show that Eq. (44.13) can be written as 1 + z =([1 + β]/[1 – β])1/2 , where β = v/c. b. The observed redshift for a certain galaxy is z
> A galaxy in the constellation Pisces is 5210 Mly from the earth. a. Use the Hubble law to calculate the speed at which this galaxy is receding from earth. b. What redshifted ratio λ0/λS is expected for light from this galaxy?
> In an experiment done in a laboratory on the earth, the wavelength of light emitted by a hydrogen atom in the n = 4 to n = 2 transition is 486.1 nm. In the light emitted by the quasar 3C273 (see Problem 36.60), this spectral line is redshifted to 563.9 n
> Section 44.5 states that current experiments show that the mass of the Higgs boson is about 125 GeV/c2. What is the ratio of the mass of the Higgs boson to the mass of a proton?
> A positive pion at rest decays into a positive muon and a neutrino. a. Approximately how much energy is released in the decay? (Assume the neutrino has zero rest mass. Use the muon and pion masses given in terms of the electron mass in Section 44.1.) b
> Figure 40.15a shows that the higher the energy of a bound state for a finite potential well, the more the wave function extends outside the well (into the intervals x L). Explain why this happens. From Figure 40.15a 40.15 (a) Wave functions for th
> Given that each particle contains only combinations of u, d, s, u, d, and s, use the method of Example 44.7 to deduce the quark content of a. a particle with charge +e, baryon number 0, and strangeness +1; b. a particle with charge +e, baryon number -1
> What is the total kinetic energy of the decay products when an upsilon particle at rest decays to τ+ + τ- ?
> Determine the electric charge, baryon number, strangeness quantum number, and charm quantum number for the following quark combinations: a. uds; b. cu; c. ddd; and d. dc. Explain your reasoning.
> Determine the electric charge, baryon number, strangeness quantum number, and charm quantum number for the following quark combinations: a. uus, b. cs, c. ddu, and d. cb.
> In which of the following reactions or decays is strangeness conserved? In each case, explain your reasoning. a. K+→ µ+ + vµ; b. n + K+→ p + π0; c. K+ + K-→ π 0 + π 0; d. p + K- →Λ0 + π 0.
> Which of the following reactions obey the conservation of baryon number? a. p + p → p + e+; b. p + n → 2e+ + e-; c. p → n + e- + ve; d. p + p → 2γ.
> In which of the following decays are the three lepton numbers conserved? In each case, explain your reasoning. a. µ- → e- + ve + vµ; b. τ- → e- + ve + vτ; c. π+ → e+ + γ; d. n → p + e- + ve .
> The discovery of the Ω- particle helped confirm GellMann’s eightfold way. If an Ω decays into a Λ0 and a K-, what is the total kinetic energy of the decay products?
> If a Σ+ at rest decays into a proton and a π0, what is the total kinetic energy of the decay products?
> Table 44.3 shows that a Σ0 decays into a Λ0 and a photon. a. Calculate the energy of the photon emitted in this decay, if the Λ0 is at rest. b. What is the magnitude of the momentum of the photon? Is it reasonable to ignore the final momentum and kinet
> It is stated in Section 40.3 that a finite potential well always has at least one bound level, no matter how shallow the well. Does this mean that as U0 0, E1 0? Does this violate the Heisenberg uncertainty principle? Explain.
> Two equal-energy photons collide head-on and annihilate each other, producing a µ+µ- pair. The muon mass is given in terms of the electron mass in Section 44.1. a. Calculate the maximum wavelength of the photons for this to occur. If the photons have th
> What is the mass (in kg) of the Z0? What is the ratio of the mass of the Z0 to the mass of the proton?
> How much energy is released when a µ- muon at rest decays into an electron and two neutrinos? Neglect the small masses of the neutrinos.
> A K+ meson at rest decays into two π mesons. a. What are the allowed combinations of π0, π+, and π- as decay products? b. Find the total kinetic energy of the π mesons.
> You work for a start-up company that is planning to use antiproton annihilation to produce radioactive isotopes for medical applications. One way to produce antiprotons is by the reaction p + p → p + p + p + p in proton-proton collisions. a. You first c
> In Example 44.3 it was shown that a proton beam with an 800-GeV beam energy gives an available energy of 38.7 GeV for collisions with a stationary proton target. a. You are asked to design an upgrade of the accelerator that will double the available ene
> Calculate the minimum beam energy in a proton-proton collider to initiate the p + p → p + p + η0 reaction. The rest energy of the h0 is 547.3 MeV (see Table 44.3). From Table 44.3 TABLE 44.3 Some Hadrons and Th
> a. what is the speed of the proton that has total energy 1000 GeV? b. What is the angular frequency ω of a proton with the speed calculated in part (a) in a magnetic field of 4.00 T? Use both the nonrelativistic Eq. (44.7) and the correct rel
> Let ωnr be the nonrelativistic cyclotron angular frequency given by Eq. (44.7), and let ωr be the corresponding relativistic value, ωr =(|q|B/m) 1−
> a. A high-energy beam of alpha particles collides with a stationary helium gas target. What must the total energy of a beam particle be if the available energy in the collision is 16.0 GeV? b. If the alpha particles instead interact in a colliding-beam
> Compare the wave functions for the first three energy levels for a particle in a box of width L (see Fig. 40.12a) to the corresponding wave functions for a finite potential well of the same width (see Fig. 40.15a). How does the wavelength in the interval
> The magnetic field in a cyclotron that accelerates protons is 1.70 T. a. How many times per second should the potential across the dees reverse? (This is twice the frequency of the circulating protons.) b. The maximum radius of the cyclotron is 0.250 m
> A neutral pion at rest decays into two photons. Find the energy, frequency, and wavelength of each photon. In which part of the electromagnetic spectrum does each photon lie? (Use the pion mass given in terms of the electron mass in Section 44.1.)
> A photon with a wavelength of 3.50 * 10-13 m strikes a deuteron, splitting it into a proton and a neutron. a. Calculate the kinetic energy released in this interaction. b. Assuming the two particles share the energy equally, and taking their masses to
> An alpha particle is strongly bound. The 6 12
> Calculate a. the total binding energy and b. the binding energy per nucleon of 12C. c. What percent of the rest mass of this nucleus is its total binding energy?
> The most common isotope of uranium, 92 238
> The most common isotope of boron is 5 11
> Consider the nuclear reaction 14 28
> Consider the nuclear reaction 2 4
> The United States uses about 1.4 * 1019 J of electrical energy per year. If all this energy came from the fission of 235U, which releases 200 MeV per fission event, a. how many kilograms of 235U would be used per year, and b. how many kilograms of uran
> A particle is confined to a finite potential well in the region 0 < x < L. How does the area under the graph of Ψ 2 in the region 0 < x < L compare to the total area under the graph of Ψ 2 when including all possible x?
> At the beginning of Section 43.7 the equation of a fission process is given in which 235U is struck by a neutron and undergoes fission to produce 144Ba, 89Kr, and three neutrons. The measured masses of these isotopes are 235.043930 u (235U), 143.922953 u
> Calculate the energy released in the fusion reaction 2 3
> Consider the nuclear reaction 1 2
> Calculate the reaction energy Q for the reaction p + 1 3
> The nuclei 5 11
> In a diagnostic x-ray procedure, 5.00 * 1010 photons are absorbed by tissue with a mass of 0.600 kg. The x-ray wavelength is 0.0200 nm. a. What is the total energy absorbed by the tissue? b. What is the equivalent dose in rem?
> In an industrial accident a 65-kg person receives a lethal whole-body equivalent dose of 5.4 Sv from x rays. a. What is the equivalent dose in rem? b. What is the absorbed dose in rad? c. What is the total energy absorbed by the person’s body? How doe
> A 67-kg person accidentally ingests 0.35 Ci of tritium. a. Assume that the tritium spreads uniformly throughout the body and that each decay leads on the average to the absorption of 5.0 keV of energy from the electrons emitted in the decay. The half-li
> It has become popular for some people to have yearly whole-body scans (CT scans, formerly called CAT scans) using x rays, just to see if they detect anything suspicious. A number of medical people have recently questioned the advisability of such scans,
> Food is often irradiated with either x rays or electron beams to help prevent spoilage. A low dose of 5–75 kilorads (krad) helps to reduce and kill inactive parasites, a medium dose of 100–400 krad kills microorganisms
> In Fig. 40.12b, the probability function is zero at the points x = 0 and x = L, the “walls” of the box. Does this mean that the particle never strikes the walls? Explain. From Fig. 40.12b (b) \W»F n = 3 n = 2 n =
> A person exposed to fast neutrons receives a radiation dose of 300 rem on part of his hand, affecting 25 g of tissue. The RBE of these neutrons is 10. a. How many rad did he receive? b. How many joules of energy did he receive? c. Suppose the person r
> A nuclear chemist receives an accidental radiation dose of 5.0 Gy from slow neutrons (RBE = 4.0). What does she receive in rad, rem, and J/kg?
> If a person’s entire body is exposed to 5.0 J / kg of x rays, death usually follows within a few days. a. Express this lethal radiation dose in Gy, rad, Sv, and rem. b. How much total energy does a 70.0-kg person absorb from such a dose? c. If the 5.0
> a. If a chest x ray delivers 0.25 mSv to 5.0 kg of tissue, how many total joules of energy does this tissue receive? b. Natural radiation and cosmic rays deliver about 0.10 mSv per year at sea level. Assuming an RBE of 1, how many rem and rads is this d
