Physics 1104 Sample Exams for Midterm 2. Two sample exams are provided for your use in preparing for your midterm 2 exam.

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1 Physics 1104 Sample Exams for Midterm 2 Two sample exams are provided for your use in preparing for your midterm 2 exam. Just like your actual midterm exam, each sample exam consists of 33 multiple choice questions. You will have 70 minutes to complete the actual 33-question midterm exam. We suggest that you give yourself 70 minutes to work each of these sample exams. Your midterm exam booklet will include a sheet of equations and constants that is similar to the equation sheet distributed in class. A key with the sample exam answers is given on the last page of this document. 1

2 Physics 1104 Sample Midterm 2A How many neutrons are in 19 K (potassium-40)? a) 2 b) 19 c) 21 d) 40 e) In a certain chemical reaction, 60 joules of energy were required to break chemical bonds, but 20 joules of energy were given off when new bonds were formed. This reaction was a) exothermic and released 40 joules of energy. b) endothermic and took in 40 joules of energy. c) endothermic and took in 20 joules of energy. d) exothermic and released 60 joules of energy. e) endothermic and took in 60 joules of energy. 3. What are the values of A and Z for the isotope A Z X produced in the reaction 4 A 86Rn 2He ZX? 222 a) A = 226 and Z = 88 b) A = 222 and Z = 86 c) A = 218 and Z = 84 d) A = 136 and Z = 84 e) A = 132 and Z = The half-life of 83 Bi (bismuth-210) is 5 days. One kilogram of bismuth-210 is placed in a sealed container. How much bismuth-210 will be left after 30 days? a) 250 grams b) 125 grams c) 62 grams d) 31 grams e) 16 grams 2

3 5. Of the following lists, which correctly lists the types of ionizing radiation in descending order of their ability to penetrate materials? a) alpha, beta, gamma b) alpha, gamma, beta c) beta, alpha, gamma d) gamma, alpha, beta e) gamma, beta, alpha 6. Which of the following is NOT an endothermic reaction? a) Water is cooled when ammonium nitrate dissolves in it. b) A battery powers a fan. c) Water molecules are split into oxygen and hydrogen. d) Photosynthesis occurs in plant cells. e) All of the above are endothermic reactions. 7. Suppose that the count rate from a radioactive substance fell from 800 counts per minute to 275 counts per minute in some time interval, t. The background radiation was determined to be 100 counts per minute. If the half life of the substance is 20 minutes, how long was the time interval, t? a) 20 minutes b) 30 minutes c) 40 minutes d) 60 minutes e) 80 minutes 8. When coal with high sulfur content is burned, oxides of sulfur are produced. This is undesirable because a) the oxides of sulfur are unstable and break apart, forming ozone, which can harm plant life. b) the oxides of sulfur combine with water vapor to form sulfuric acid. c) the oxides of sulfur combine with hydrocarbons to form carbon monoxide. d) the oxides of sulfur combine with nitrogen in the atmosphere to produce the chemicals responsible for smog. e) of the economic consequences of using the limited supply of coal in the U.S. 3

4 The mass of a 92 U nucleus is x kilograms. What is the binding energy of this uranium nucleus? a) x J b) x J c) x J d) 7.62 J e) 1791 x 10 6 J 10. In which layer of the Earth s atmosphere is the protective ozone layer located? a) troposphere b) stratosphere c) ionosphere d) hydrosphere e) aerosphere 11. Potassium-argon dating can be used to date volcanic rock between 400,000 and ,000,000 years old. The relevant nuclear reaction is K Ar. What type of decay is this? a) alpha decay b) beta-plus decay c) beta-minus decay d) gamma decay e) neutron decay e Isotopes are nuclei with the same a) number of neutrons. b) number of protons. c) number of electrons. d) total number of neutrons and protons. e) total number of neutrons, protons, and electrons. 4

5 13. A procedure that may be used to determine whether or not a system is sensitive is to observe two models of the system with very similar initial conditions. The system is sensitive if which of the following is TRUE? a) Both models behave predictably. b) Both models behave identically after some time. c) Both models behave very differently after some time. d) Both models have many moving parts. e) The system can be simulated by a computer program. 14. An electrostatic precipitator is effective in removing which of the following pollutants from smokestack emissions? a) ozone b) oxides of nitrogen c) oxides of sulfur d) fine particulate matter e) An electrostatic precipitator is effective in removing all of the above from smokestack emissions. 15. In a chemical reaction, a) energy is always given off. b) molecules may change phase, but no molecules are created or destroyed. c) molecules may be created or destroyed, but no atoms are created or destroyed. d) atoms may be created or destroyed, but no nucleons are created or destroyed. e) nucleons are created or destroyed How many neutrons must change into protons for a 14 Si nucleus to become 40 a more stable 20 Ca nucleus? a) 1 b) 3 c) 6 d) 14 e) 26 5

6 17. The purpose of control rods in a fission reactor is a) to serve as a catalyst that controls the rate of the reaction. b) to slow down neutrons to energies appropriate for inducing fission in uranium-235. c) to supply the activation energy to start the reaction. d) to absorb neutrons and control the rate at which the fission reaction occurs. e) to cool the uranium as it melts. 18. A cloud chamber is a a) device for testing predictions of the greenhouse effect. b) device for testing predictions of depletion of ozone in the atmosphere. c) device that ionizes smoke particles that pass through it. d) device for showing the tracks left by ions. e) component of nuclear smoke detectors. 19. The amount of radiation exposure a given person receives in a year depends on all of the following EXCEPT a) the altitude at which the person lives. b) the number of X-rays received during the year. c) the amount of potassium ingested in food. d) the geographical locations where the person spends time. e) The amount of radiation exposure depends on all of these factors. 20. In chemical reactions, the amount of mass that might be converted into energy is very small. In nuclear reactions this is not the case because a) the binding energy in chemical bonds is much larger than in nuclear bonds. b) the binding energy in nuclear bonds is much larger than in chemical bonds. c) the binding energy in chemical bonds and in nuclear bonds is the same, but many more chemical reactions take place. d) the binding energy for chemical bonds depends on the catalyst present, while nuclear bonds are the same for all nuclei. e) the binding energies for chemical bonds and nuclear bonds are almost the same, except for heavy nuclei that fission. 6

7 21. Which of the following did NOT happen in the Chernobyl power plant accident? a) Human error resulted in an uncontrolled chain reaction and a rapid increase in temperature. b) An explosion caused by the sudden vaporization of water blew the concrete lid off of the reactor core. c) A chemical reaction tore away one quarter of the reactor core. d) A fusion reaction explosion (like that in a hydrogen bomb) destroyed the reactor building. e) Radioactive dust was released into the atmosphere. 22. How are the Milankovitch cycles related to climate? a) They can predict the Earth s weather each year. b) They are used to forecast El Nino storm patterns. c) They can explain past glacial ice ages. d) They can predict solar flares and sun spots. e) None of the above is correct. 23. Which of the following statements regarding computer simulations is TRUE? a) Computer simulations are unbiased. b) Computer simulations can handle fewer calculations than a human could. c) Computer simulations are more complicated than the actual situation. d) Computer simulations can be used to model situations that have many parts to them. e) Computer simulations can always be used to make very accurate predictions. 24. Ionizing radiation can a) be used to diagnose cancer. b) be used to treat cancer. c) cause cancer. d) All of the above are true. e) Only b) and c) are true. 7

8 25. Which of the following statements about ozone is TRUE? a) Ozone is harmless since it is made entirely of oxygen. b) Ozone reduces smog in the lower atmosphere. c) Ozone in the lower atmosphere is harmful, since it can combine with other pollutants to produce smog. d) If the ozone layer is too thick, it will result in an increase in cases of skin cancer. e) If the ozone layer is too thick, it will result in global warming. 26. Which of the quark diagrams shown below could correctly represent a proton? a) b) d u u d u u c) d) u d d u d d 8

9 27. Why is carbon monoxide dangerous? a) It contributes to global warming. b) It destroys the Earth s protective ozone layer c) It is a major component of acid rain. d) It can cause fatal oxygen deprivation in humans. e) Both b) and d) are correct. 28. The chemical identity of an element is determined by its number of a) electrons. b) protons. c) nucleons d) neutrons e) Both b) and d) are correct. 29. Feedback loops play a role in the enhanced greenhouse effect. Which of the following is an example of a negative feedback loop? a) Increasing ocean temperatures result in more dissolved carbon dioxide released into the atmosphere. b) Combustion of fossil fuels releases soot into the atmosphere, which reflects incoming sunlight back into space. c) The melting of ice sheets at high latitudes allows more photons of sunlight to be absorbed by the Earth s surface. d) Melting permafrost releases methane gas produced by the decay of plant and animal materials. e) All of the above are examples of positive feedback loops. 30. Which of the following nuclear reactor designs is the safest? a) fuel rods, water modulated, water cooled b) fuel rods, graphite modulated, water cooled c) fuel pellets, water modulated, gas cooled d) the reactor designs described in a) and b) are the safest e) All of the above designs are equally safe. 9

10 31. What is a gluon? a) a force that glues molecules together b) an isotope of carbon c) a quark that has no spin d) a gauge boson that produces the strong nuclear force e) a glue stick of super glue 32. According to the video Beyond the Light Switch, Part 2, which of the following was a green energy initiative of President Carter in the 1970 s? a) solar panels on the roof of the White House b) wind turbines on the top of the Washington monument c) a vegetable garden on the White House lawn d) biodiesel peanut oil used in government vehicles e) All of the above were green energy initiatives described in the video. 33. According to the video Extreme Ice, how did the ice survey team measure the speed of the Columbia glacier s movement? a) attach a speedometer to the ice b) have a survey team member camp on the ice c) aim lasers at targets embedded in the ice d) rappel into a crevice in the ice e) measure the amount of melt water from the glacier 10

11 Sample Midterm 2B 1. Which of the following could expose you to ionizing radiation? a) potassium iodide (salt substitute) b) an old orange Fiestaware dish c) wearing a radium wrist watch d) uranium and thorium ores e) All of the above could expose you to ionizing radiation Neptunium-239 ( 93 Np ) decays by beta-minus decay and becomes 239 a) Thorium-239 ( 90 Th) 234 b) Radium-234 ( 88 Ra ) 238 c) Uranium-238 ( 92 U ) 239 d) Plutonium-239 ( 94 Pu) 235 e) Radium-235 ( 88 Ra ) 3. Three sealed beakers contain an identical mass of some substance. Substance A undergoes a physical change that gives off energy. Substance B undergoes a chemical change that gives off energy. Substance C undergoes a nuclear change that gives off energy. In each case, no physical matter was allowed to escape from the beaker. Which of the following statements is true? a) Each beaker still contains the same mass as it did before the change. b) Each beaker now contains less mass than it did before the change. c) Each beaker now contains more mass than it did before the change. d) Beaker C now contains less mass than it did before the change, but beakers A and B still contain the same mass as before. e) Beakers B and C now contain less mass than they did before the change, but beaker A still contains the same mass as before. 11

12 4. In a certain chemical reaction, reactants A + B react to give products C + D. The reaction is exothermic. What must be true about the reverse reaction: C + D react to give A + B? a) The reverse reaction requires activation energy. b) The reverse reaction must be endothermic. c) The reverse reaction will require a catalyst. d) Both a) and b) must be true. e) The reverse reaction cannot happen, since no chemical reaction can ever be reversed What particle X is emitted in the reaction: Th Ra X? a) an electron b) an antielectron c) a neutrino d) an alpha particle e) All of the above will be emitted Which of the following statements is TRUE? a) All radioactive elements are human-made (not naturally occurring). b) Microwave ovens use a radioactive source to cook food. c) Radiation can expose a piece of photographic film. d) The majority of ionizing radiation present in the environment results from the operation of nuclear power plants. e) NONE of the above statements is true 7. If 5 kilograms of matter could be entirely converted into energy, how much energy would this be? a) 5 J b) 49 J c) 1.5 x 10 9 J d) 1.5 x J e) 4.5 x J 12

13 8. Which of the following statements is CORRECT? a) Catalysts can only be used in endothermic reactions. b) Catalysts can only be used in exothermic reactions. c) Only endothermic reactions require activation energy. d) Only exothermic reactions require activation energy. e) NONE of the above statements is correct. 9. Which of the following is NOT a factor that affects how well a computer simulation will predict future behavior of a physical system? a) the sensitivity of the system to initial conditions b) the computer hardware used in the simulation c) the validity of the system s data d) how well the model of the system represents the system. e) ALL of the above factors can influence the accuracy of the simulation. 10. The half-life of an unstable isotope is 5 minutes. If a sample of this isotope gives 800 counts per minute above the background now, what will be count rate from this isotope 15 minutes from now? a) 800 cts/ min b) 400 cts/min c) 200 cts/min d) 100 cts/min e) 50 cts/min 11. Which of the reactions given below is/are correctly balanced? a) H2 O2 H2O b) H2 2O2 2H2O c) 2H2 O2 2H2O d) All of the reactions are balanced. e) None of the reactions is balanced. 13

14 12. When a light shines through a pegboard with evenly spaced holes and onto a globe, what do you see? a) spots of light more closely spaced at the globe s higher latitudes b) spots of light more closely spaced in the globe s southern hemisphere c) spots of light evenly spaced across the globe d) spots of light more closely spaced at the globe s equator e) spots of light distributed chaotically 13. Which of the following reactions correctly shows the decay of carbon-14? a) C Be He o b) C B 6 5 1e o c) C N 6 7 1e d) C N o 6 7 1e e) C C o 6 6 1e 2 o o o o 14. Which of the following types of particles is important in setting up a nuclear chain reaction? a) Electrons b) Protons c) Neutrons d) Alpha particles e) Beta particles 15. In a nuclear reaction, which of the following quantities are conserved? a) neutron number, charge, and entropy b) proton number, charge, and entropy c) nucleon number, energy, and entropy d) energy, charge, and nucleon number e) energy, entropy, and charge. 14

15 16. Which of the following statements about the greenhouse effect is TRUE? a) Burning high sulfur coal is the main cause of the greenhouse effect. b) The greenhouse effect occurs when carbon dioxide in the atmosphere absorbs ultraviolet light. c) The greenhouse effect is increased when green plants release oxygen into the atmosphere. d) The greenhouse effect is increased by larger concentrations of carbon dioxide and water vapor in the atmosphere. e) None of the statements is true. 17. Which of the following is NOT a way to reduce your exposure to radiation? a) move to a lower elevation b) vent radon from your home c) travel by air rather than car for long trips d) avoid brick and stone as building materials e) avoid X-rays 18. Which of the following combinations of quarks could produce a nucleon? a) Three up quarks b) Three down quarks c) Two up quarks and one down quark d) One up quark and two down quarks e) Both c) and d) could produce a nucleon 19. Which of the following could NOT be emitted in radioactive decays? a) gamma rays b) helium nuclei c) electrons d) antielectrons e) All of the above can be emitted in radioactive decays. 15

16 20. The catalytic converter in automobiles a) speeds up the decomposition of oxides of nitrogen. b) speeds up photochemical reactions. c) removes oxides of sulfur from the exhaust. d) filters suspended particles from the exhaust. e) absorbs ozone. 21. Which of the following conditions could result in an inversion layer? a) A layer of warm air lies over a layer of cool air. b) A layer of cool air lies over a layer of warm air. c) A layer of hydrocarbon particles lies over warm air. d) A layer of cold air containing acid rain lies over a layer of air containing hydrocarbon particles. e) A layer of ozone lies over a layer of carbon dioxide. 22. Alpha particle radiation is a) emission of electrons from a radioactive source. b) emission of photons from radioactive material. c) emission of helium nuclei from radioactive material. d) made up of two protons and three neutrons. e) not dangerous. 23. Which of the following is NOT a part of most U.S. nuclear reactors? a) moderator b) control rods c) water coolant d) fuel rods e) ALL of the above are used in most U.S. nuclear reactors. 16

17 24. Which of the following does NOT represent a deterministic system? a) a swinging pendulum b) a bouncing tennis ball c) wind gusts d) water flowing in a stream e) All of the above are deterministic systems. 25. Which of the following does NOT contribute to the production of photochemical smog? a) oxides of nitrogen b) oxides of sulfur c) hydrocarbons produced by the incomplete combustion of gasoline d) ultraviolet photons from the sun e) All of the above contribute to the production of photochemical smog. 26. Which of the following statements about breeder reactors is TRUE? a) Breeder reactors do not need control rods. b) Breeder reactors use concentrated strontium-60 for fuel. c) Breeder reactors use fast neutrons, so no moderator is needed. d) Breeder reactors make more plutonium than they use as fuel. e) Both c) and d) are true. 27. Which of the following is NOT a likely consequence of the use of chemical energy? a) global warming b) acid rain c) depletion of the ozone layer d) particulate pollution e) All of the above are consequences of the use of chemical energy. 17

18 28. Which of the following is the primary product of the complete combustion of gasoline in an automobile engine? a) soot (carbon) b) carbon monoxide c) carbon dioxide d) hydrocarbons e) sulfur oxides 29. Which of the following is NOT a method used for determining prehistoric climate? a) ice cores b) tree rings c) lake and sea sediments d) uranium ore samples e) All of the above can be used to determine prehistoric climates. 30. A galaxy is located 5.5 x meters from Earth. How long will light take to travel from this galaxy to Earth? a) 6.1 x 10 8 sec b) 1.83 x sec c) 1.6 x sec d) 4.5 x sec e) 1.8 x sec 31. What was the cause of the Fukushima nuclear reactor accident? a) A tsunami wave of water inundated the reactor. b) The backup generators were flooded and failed. c) No coolant was present to remove heat from the reactor. d) Hydrogen gas trapped in the reactor buildings exploded. e) All of the above contributed to the Fukushima accident. 18

19 32. Which of the following statements about the Earth s energy balance is TRUE? a) Most of the energy emitted by the Sun is absorbed by the Earth s surface. b) The Earth absorbs mainly infrared energy from the Sun and emits microwave radiation. c) The enhanced greenhouse effect is due to increased oxygen production by green plants. d) Any amount of greenhouse gas in the atmosphere is harmful. e) The Earth s energy balance requires that all of the incoming solar radiation is eventually radiated back into space. 33. Which of the following statements about sensitive systems is TRUE? a) Sensitive systems are deterministic, but insensitive systems are not. b) Sensitive systems do not follow Newton s Laws of motion. c) Sensitive systems can be greatly influenced by changes in initial conditions. d) Sensitive systems do not exist in nature. e) None of the above statements is true. 19

20 Answers to Sample Midterms 2 Question Number Midterm 2A Answers 1 c e 2 b d 3 c b 4 e d 5 e d 6 b c 7 c e 8 b e 9 c b 10 b d 11 b c 12 b d 13 c d 14 d c 15 c d 16 c d 17 d c 18 d e 19 e e 20 b a 21 d b 22 c c 23 d e 24 d e 25 c b 26 b e 27 d e 28 b c 29 b d 30 c b 31 d e 32 a e 33 c c Midterm 2B Answers 20