MODERN PHYSICS. A. s c B. dss C. u

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "MODERN PHYSICS. A. s c B. dss C. u"

Transcription

1 MODERN PHYSIS Name: Date: 1. Which color of light has the greatest energy per photon? 4. The composition of a meson with a charge of 1 elementary charge could be. red. green. blue D. violet. s c. dss. u b D. u c d 2. Light of constant intensity strikes a metal surface. The frequency of the light is increased from cycles per second to cycles per second. Photoelectrons are emitted by the metal surface when the frequency reaches cycles per second. s the frequency of the incident light increases, the photons striking the metal surface increase in. number. energy. speed D. wavelength 3. If the intensity of the incident light were increased while the frequency was kept constant, the maximum kinetic energy of the emitted photoelectrons would. decrease. increase. remain the same 5. ase your answer(s) to the following question(s) on the information below. Two experiments running simultaneously at the Fermi National ccelerator Laboratory in atavia, Ill., have observed a new particle called the cascade baryon. It is one of the most massive examples yet of a baryon a class of particles made of three quarks held together by the strong nuclear force and the first to contain one quark from each of the three known families, or generations, of these elementary particles. Protons and neutrons are made of up and down quarks, the two first-generation quarks. Strange and charm quarks constitute the second generation, while the top and bottom varieties make up the third. Physicists had long conjectured that a down quark could combine with a strange and a bottom quark to form the three-generation cascade baryon. On June 13, the scientists running Dzero, one of two detectors at Fermilab s Tevatron accelerator, announced that they had detected characteristic showers of particles from the decay of cascade baryons. The baryons formed in proton-antiproton collisions and lived no more than a trillionth of a second. week later, physicists at DF, the Tevatron s other detector, reported their own sighting of the baryon... Source: D.., Pas de deux for a three-scoop particle, Science News, Vol. 172, July 7, 2007 Which combination of three quarks will produce a neutron? page 1

2 6. What is the magnitude and sign of the charge, in elementary charges, of a cascade baryon? 9. Which graph best represents the relationship between photon energy and photon frequency?.. 7. ompared to the mass and charge of a proton, an antiproton has. the same mass and the same charge. greater mass and the same charge.. the same mass and the opposite charge D. greater mass and the opposite charge D. 8. particle that is composed of two up quarks and one down quark is a. meson. neutron. proton D. positron page 2 MODERN PHYSIS

3 10. variable-frequency light source emits a series of photons. s the frequency of the photon increases, what happens to the energy and wavelength of the photon?. The energy decreases and the wavelength decreases.. The energy decreases and the wavelength increases.. The energy increases and the wavelength decreases. D. The energy increases and the wavelength increases. 13. ase your answer(s) to the following question(s) on the data table below. The data table lists the energy and corresponding frequency of five photons. Photon Energy (J) Frequency (Hz) D E In which part of the electromagnetic spectrum would photon D be found?. infrared. visible. ultraviolet D. x ray 11. The slope of a graph of photon energy versus photon frequency represents. Planck s constant. the mass of a photon. the speed of light D. the speed of light squared 14. The energy of a photon is inversely proportional to its. wavelength. speed. frequency D. phase 12. ll photons in a vacuum have the same. speed. wavelength. energy D. frequency 15. How many neutrons are there in U? D. 327 page 3 MODERN PHYSIS

4 16. The number of nucleons in the nucleus of a 14 6 atom is 20. Since charge must be conserved in the reaction shown, what charge must an electron antineutrino carry? D Which type of force causes the hyperbolic trajectory of alpha particles in Rutherford s scattering experiment?. gravitational. electrostatic. magnetic D. nuclear 21. ccording to the Standard Model, a proton is constructed of two up quarks and one down quark (uud) and a neutron is constructed of one up quark and two down quarks (udd). During beta decay, a neutron decays into a proton, an electron, and an electron antineutrino. During this process there is a conversion of a. u quark to a d quark 18. n excited hydrogen atom returns to its ground state. possible energy change for the atom is. loss of ev. gain of ev. d quark to a meson. baryon to another baryon D. lepton to another lepton. loss of 3.40 ev D. gain of 3.40 ev 19. ase your answer(s) to the following question(s) on the information and equation below. During the process of beta (β ) emission, a neutron in the nucleus of an atom is converted into a proton, an electron, an electron antineutrino, and energy. neutron proton + electron + electron antineutrino + energy 22. s a photon loses energy during a collision, its wavelength. decreases. increases. remains the same ased on conservation laws, how does the mass of the neutron compare to the mass of the proton? page 4 MODERN PHYSIS

5 23. What is conserved in a photon-particle collision?. mass, only. energy, only. momentum, only D. mass, energy, and momentum 26. ase your answer(s) to the following question(s) on the information below. lambda particle consists of an up, a down, and a strange quark. lambda particle can be classified as a. baryon. lepton. meson D. photon 24. Which phenomenon is most easily explained by the particle theory of light?. photoelectric effect. constructive interference. polarization D. diffraction 27. ccording to the Standard Model of Particle Physics, a meson is composed of. a quark and a muon neutrino 25. In an experiment, Ernest Rutherford observed that some of the alpha particles directed at a thin gold foil were scattered at large angles. This scattering occurred because the. a quark and an antiquark. three quarks D. a lepton and an antilepton. negatively charged alpha particles were attracted to the gold s positive atomic nuclei. negatively charged alpha particles were repelled by the gold s negative atomic nuclei. positively charged alpha particles were attracted to the gold s negative atomic nuclei D. positively charged alpha particles were repelled to the gold s positive atomic nuclei page 5 MODERN PHYSIS

6 Problem-ttic format version c Educide Software Licensed for use by Terms of Use at MODERN PHYSIS 5/17/ D D up, down, down. 25. D 6. 1e Neutron is more massive. 20. The charge on the electron antineutrino is zero or neutral.