PHYSICS Knowledge Survey

Spring 2008
This is a knowledge survey rather than a test. The purpose of this survey is to serve as a study guide and to help you and the instructor evaluate the change produced in your knowledge by this course. In this knowledge survey, you won't actually try to answer any of the questions provided. Instead, you will rate (on a three-point scale) your confidence to answer the items based on you your present knowledge. Read each question and then respond by clicking the appropriate response button on Web in accord with the following rating.


Mark an "A" as response ONLY if you feel confident that you can now answer the question sufficiently for graded test purposes. Mark a "B" response to the question if you can now answer at least 50% of it or if you know precisely where you could quickly get the information needed and could return here in 20 minutes or less to provide a complete answer for graded test purposes. Mark a "C" as response to the question if you are not confident that you could adequately answer the question for graded test purposes at this time. These marking of an "A" "B" or "C" will go quickly after you get the hang of responding based on confidence. Accurate self-assessment is a practical skill that is more important than even current content knowledge. It is important to make an accurate self-assessment so that you can obtain the best learning enhancement from a knowledge survey. What constitutes a successful response to this survey is an accurate self-assessment, one that neither overestimates nor underestimates the knowledge that you now currently have. Do your best to provide a very honest assessment of your present knowledge. If you mark an "A" or a "B" that states you have significant background to answer a question, you should be confident that if your professor asks you to demonstrate that ability by actually answering the so-designated questions, that you could actually respond for graded test purposes. This survey will be given again at the end of the semester. Save/print the survey and refer to the items as we progress through the course in order to monitor your increasing mastery of the material as we proceed through the semester.

Please answer all the questions in one sitting. It should take you about 15 minutes to complete the survey.

Please fill in your name and select the appropriate class section before completing the survey.

Student Name:
Physics Section:
1. Describe the basic method of science and provide one example of its application.
2. What’s a hypothesis? Provide two examples of testable hypotheses, and an example of an untestable hypothesis.
3. Provide two specific examples that illustrate why it is important to the everyday life of an educated person to be able to understand science.
4. Describe two current examples of the relationship between physical science and public policy.
5. With respect to the scientific method, what happens to hypotheses that are proven in correct? A. They become theories B. They are discarded C. They are recycled into other projects. D. They are tested through theories. E. They are guessed at in an educated fashion.
6. In daily life, we see many cases of people who are caught misrepresenting things and who soon thereafter are excused and accepted by their contemporaries. How is this different in science?
7. Distinguish between speed and velocity.
8. One type of home coffee grinder has a small blade that rotates very rapidly and cuts the beans into powder. Nothing prevents the beans from moving, so why don’t the coffee beans get out of the way when the blade begins to push on them?
9. A speedboat is pulling a water-skier with a rope, exerting a large force on her. The skier is traveling forward in a straight line at constant speed. What is the net force she experiences?
10. When a car moves down the road at constant velocity, the net force on it is zero. Why then do you continue running your engine?
11. Find the net force produced by a force of 10-N and a force of 6-N when (a) they act in the same direction and (b) when they act in opposite directions
12. When a book sits on a table, what forces act on the book?
13. You are whirling a ball on a string in a horizontal circle (see figure). If the string breaks when the ball is in the position shown, which arrow shows the path the ball will follow immediately afterward? a___, b___, c___, d ___?
14. How much tension is there in a rope the holds a 20-N bag of apples at rest?
15. Distinguish between velocity and acceleration.
16. What relationship does mass have with weight?
17. Does a stick of dynamite contain force?
18.  A 50kg crate has an acceleration of 3 m/s2. What is the net force on the object?
19. You push horizontally on a crate but it does not move (see figure below). How does the friction force acting on the crate compare with your push?
20.  You push horizontally harder on the crate. It starts to move. Once the crate is moving, how hard do you have to push to keep the crate moving with constant velocity?
21. You are pulling a 50 kg crate across the floor with a horizontal rope (see figure below). You exert a force of 130 N on the rope and the floor exerts a friction force of 30 N. (a) What is the net force acting on the crate? (b) What is the acceleration of the crate?
22. What is meant by “terminal velocity”?
23. If the earth pulls you downward, what is the reaction force?
24. When you kick a soccer ball, which pushes on the other harder, your foot or the soccer ball?
25. Two teams are having a tug-of-war. Your friend says, “The team that pulls harder on the rope wins.” How do you answer him? What does the winning team have to do better to win?
26. The horse refuses to pull the wagon, saying it would be futile because of Newton’s Third Law. He argues that if he can’t exert more force on the wagon than the wagon exerts on him, he won’t be able to get the wagon moving. What is your explanation to convince the horse to pull.
27. Use Newton’s Third Law to explain how a swimmer pushes off the side of a swimming pool. (What force accelerates the swimmer?)
28. When does the reaction force act? (a) before the reaction force, (b) at the same time as the reaction force (b), (c) slightly after the reaction force, (d) a long time after the reaction force
29. Earth exerts of force of 500,000 newtons on an orbiting communications satellite. Is the force that the satellite exerts on the earth greater than, equal to, or less than 500,000 newtons? Explain.
30. If a massive truck and a small sports car have a head-on collision, upon which vehicle is the impact force greater? Which vehicle experiences the greater acceleration? Explain your answers.
31. What is meant by “conservation” as used in science? How is this different from the ways that it is used in everyday English?
32. Which has the larger momentum, a heavy truck that is parked or a small car that is moving?
33. Why is skiing into a wall of deep powder less hazardous to your health than skiing into a wall of bricks? Assume in both cases you that you have the same initial speed and come to a complete stop. Explain your answer in terms of impulse and momentum.
34. A cue ball hits a stationary eight ball on a pool table. For which of the following systems is there a change in momentum during the collision? (Explain why) (a.) the cue ball, (b). the eight ball, (c). both balls
35.  A box car going 6 m/s runs into an identical box car which is sitting stationary on the track. The two cars couple together. How fast are they moving immediately after the collision?
36. Imagine you are stranded in the middle of a patch of absolutely frictionless ice. You are not moving. (a.) Explain why, no matter how you wiggle, you cannot move yourself to the edge.(b). Explain how you could get to the edge by throwing a shoe.
37. Give two examples in which a force is exerted on something but does no work.
38. How much work is done in lifting up a 50kg sack of potatoes a distance of 2 m?
39. How does the kinetic energy of a car going 60 mph compare to the kinetic energy of the same car going 30 mph?
40. Consider an ordinary, gasoline-powered car. What becomes of the kinetic energy of the car when it stops (a) by braking on a level road, and (b) by rolling up a hill in neutral until it stops?
41. Can a machine multiply input force? Input distance? Input energy?
42. When you run up a flight of stairs, do you do less, more, or the same amount of work compared to walking up the same stairs? Is your power greater, less, or the same when you run?
43. Under what conditions is energy conserved?
44. Two identical collision cars on a frictionless track have equal and opposite velocities. They also have Velcro on their ends so that when they collide they stick together and remain motionless on the track. (a). Is momentum conserved in this collision? Explain. (b). Is kinetic energy conserved in this collision? Explain.
45. How does the gravitational force between two bodies change when the distance between them is doubled?
46. If the tangential velocity of the moon were zero, how would the moon move?
47. Why does an astronaut riding in an orbiting space shuttle feel weightless? The sun exerts a larger gravitational force on the earth than the moon does. However, the moon has a greater effect on the tides. Why?
48. The sun exerts a larger gravitational force on the earth than the moon does. However, the moon has a greater effect on the tides. Why?
49. You and your friend are standing on a cliff above a flat field, At the same instant, you drop a ball and your friend throws a ball horizontally. Which ball will land first, or will they land at the same time? Neglect air resistance. Explain your answer.
50. You can throw a ball with a certain speed. To make it go the greatest possible distance, you need to aim at neither a high angle nor nearly horizontal, but in between. Explain. (Ignore air resistance)
51. At what point in its trajectory does a batted baseball have the minimum velocity? Neglecting air resistance, how does that minimum velocity compare with its horizontal velocity at other points in its trajectory? What is the ball’s acceleration at that point? (Again, neglecting air resistance)
52. Why does the speed of a satellite change as it moves in an elliptical orbit?
53. How much time would a satellite take for one complete orbit near the surface of the earth (if it didn’t have to worry about air resistance or hitting mountains)?
54. What is meant by “escape speed”?
55. Distinguish between heat and temperature.
56. Which has more thermal energy, an iceberg or a cup of hot coffee? Explain
57. If you wish to warm 100 kg of water for your bath by 20oC, how much heat is equired. Give your answer in calories and in joules.
58. How is the First Law of Thermodynamics related to the conservation of energy.
59.  A circular disk is cut out of a metal plate as shown. When the plate is heated, does the hole get bigger or smaller?
60. Desert sand is very hot in the daytime and very cold at night. What does this tell us about its specific heat capacity?
61. How is the thermal expansion and contraction of water unusual and why is it important for life on earth?
62. How does the second law of thermodynamics relate to the direction of heat flow?
63. Why does a tile floor feel colder to your feet than the bathroom rug which has been lying on the tile floor all night?
64. Two houses are next door to each other in a cold climate. One has snow on the roof and the other doesn’t. What is different about the two houses?
65. Why does your hand feel hotter several inches above a candle flame than it does several inches to the side of the candle flame?
66. Which normally cools faster: a black pot of hot water or a silver-colored pot of hot water? Explain.
67. Explain how evaporation cools the liquid left behind.
68. Why is steam at 100oC more dangerous to your hand than water at the same temperature?
69. How does a vacuum bottle minimize heat transfer by conduction, convection, and radiation?
70. All objects continuously emit radiant energy. Why then doesn’t the temperature of all objects continuously fall?
71. How is Coulomb’s Law similar to Newton's Law of Gravitation? How is it different?
72. How does an electrically polarized object differ from an electrically charged object?
73. When you comb your hair, you transfer electrons from your hair to the comb. Is your hair then positively charged or negatively charged? How about the comb? Will the comb attract or repel your hair?
74. Below is a diagram of a light bulb and a diagram of a battery. Use lines to represent wires. Draw in wires to connect the battery and the light bulb so that the light bulb will light.
75. Draw a circuit with two lights and a battery, with the light bulbs in series. How does the current through the first bulb compare with the current through the second? Does it matter if the light bulbs are identical? How does the voltage across the first bulb compare with the voltage of the battery?
76. The diagram below shows three light bulbs, labeled A, B, and C, in sockets and wired to a battery as shown. What will happen to the brightness of bulbs A and B if bulb C burns out?
77. How much current flows through a radio speaker with a resistance of 8O when 12 V is impressed across the speaker?
78. If a current of 1.5 amps flows through a flashlight bulb when it is connected to batteries with a combined voltage of 3V, how much power is the bulb consuming?
79. In what way are magnetic poles very different from electric charges? In what way are they alike?
80. Why are some pieces of iron magnets and some not?
81. What is the shape of the magnetic field lines about a current-carrying wire?
82. What must change in order for electromagnetic induction to occur? What are three ways that a voltage can be induced in a loop of wire?
83. What is the basic difference between a motor and a generator? What is the basic similarity between them?
84. “An electron always experiences a force in an electric field, but no always in a magnetic field.” Defend this statement.
85. Why is a generator armature harder to rotate when it is connected to a circuit and supplying electric current?
86. What is it that moves from source to receiver in wave motion?
87. How is the frequency of a vibration related to its period?
88. How is the wavelength of a wave related to its frequency and wave speed?
89. A slinky can transmit both longitudinal and transverse waves. How would start a longitudinal wave in a stretched slinky? A transverse wave?
90. Why will sound waves not travel in vacuum?
91. A weight suspended from a spring bobs up and down over a distance of 20 cm twice each second. What is its frequency? Its period? Its amplitude?
92. In terms of wavelength, how far does a wave travel during one period?
93. An ocean depth-sounding vessel surveys the ocean bottom with ultrasonic sound waves that travel at 1530 m/s in sea water. How deep is the water if the time delay of the echo from the ocean floor is 6 s.
94. Distinguish between forced vibrations and resonance.
95. What kind of waves exhibit interference?
96. Distinguish between constructive interference and destructive interference.
97. Describe how you would use beats between a pitch pipe and a string to tune the string.
98. Why does the sound of a train’s whistle seem to change pitch as the train passes you?
99. What is the principal difference between a radio wave and light?
100. List the ways that light is different from sound?
101. Light can an have an infinite number of different wavelengths. Why do we say there are three primary colors of light?
102.  A combination of red light and green light appears yellow, without any light at all from the yellow region of the spectrum Explain how this occurs.
103. What determines whether a material is transparent or opaque?
104.  Why are the primary colors of light different from the primary colors of pigment?
105. Why do garments that match under fluorescent light often not match in sunlight, and vice versa?
106. What color does red cloth appear when illuminated by sunlight? By red light from a neon sign? By cyan light?
107. Why is the sky blue?
108. Why does the sun appear orange or red at sunset?
109. Why do clouds appear white?
110. In the drawing below, an eye at point P is looking into the small mirror. Which number card does it see reflected in the mirror? Explain.
111. How tall must a mirror be compared to your height for you to see yourself from head to toe?
112. How does the change of speed of a ray of light affect its direction as it passes from one medium into another?
113. Distinguish between a converging lens and a diverging lens.
114. What is the focal length of a lens?
115. Distinguish between a real image and a virtual image.
116. Can you take a photograph of a rainbow? Can you take a flash photograph of a rainbow?
117. A rainbow viewed from an airplane may form a complete circle. Where will the shadow of the airplane appear?
118. Why do radio waves diffract around building but visible light waves do not?
119. What causes the colors we see in soap bubbles?
120. Polarized light is part of nature, but polarized sound is not. Why?
121. When unpolarized light is incident at a grazing angle on water, what can you say about the reflected light?
122. What evidence can you give for the wave nature of light? For th particle nature of light?
123. When does light behave like a wave? When does it behave like a particle?
124. You may assume that you have access to a periodic table in answering all the remaining questions in this knowledge survey. The number of different elements in the world is about (a) 4; (b) 10; (c) 100 or (d) several thousand
125. Distinguish between an element and a compound.
126. Distinguish between a compound and a mixture.
127. The nucleus of an atom contains ______________________ and _____________________.
128. Which atom an element belongs to is determined by the number of _____________________.
129. The number of electrons in an atom is equal to the number of ______________________.
130. How many protons are in there in an atom of carbon-14? __________________________.
131. How many neutrons are there in an atom of carbon-14? __________________________
132. As you move across a row in the periodic table, each element has one more ______________ in each atom than the one before.
133. Atoms of the same element with different numbers of neutrons are different ______________.
134. Nonmetals are found on the _________________ side of the periodic table.
135. Which has more mass, and atom of fluorine (F) or an atom of chlorine (Cl) ?
136. What is meant by a conceptual model?
137. Why are atoms invisible to visible light?
138. How can you tell a sodium vapor lamp from a mercury vapor lamp?
139. What happens to an electron as it absorbs a photon of light?
140. What is the relationship between the light emitted by an atom and the energies of the electrons in the atom.
141. How many electrons are in each shell of: Na (atomic number 11), Chlorine (atomic number 17), Silicon (atomic number 14)?
142. How is the number of filled and partially filled shells in an atom of a given element related to the row of the periodic table in which it is found?
143. Explain and give examples of physical changes and chemical changes.
144. When oxygen gas takes part in a chemical reaction, we represent the oxygen by O2. What does the 2 written as a subscript represent, and why do we use "O2" instead of just "O?"
145. What is the purpose of coefficients in a chemical equation?
146. What physical and chemical changes occur when a wax candle burns?
147. A pot of water sits on a cold stove. There is no water on the outside, even after it has sat for a while. Now you turn the gas flame on under the pot and pretty soon you notice water condensing on the outside of the pot. Where is the water coming from?
148. Fill in numbers in the blanks to balance the chemical equation for the formation of ammonia from hydrogen and nitrogen.
149. A material which consists of several substances, each retaining its own chemical identity, is a ________________________.
150. A material in which several elements combine to form a new substance with its own distinct properties is ______________________.
151. If two substances can be separated by filtration or distillation, they were in a _________________ (mixture or compound)
152. List as many physical means of separating a mixture as you can.
153. What distinguishes a solution from other mixtures?
154. 602,000,000,000,000,000,000,000 of anything is called a ________________.
155. Why is drinking water considered a mixture?
156. Which picture shows an element? A compound? A mixture?
157. The electrons in the outermost, partially filled shell of an atom are its ______________ electrons.
158. Draw electron dot structures for Beryllium (Be), Carbon (C), and Chlorine (Cl)
159. A bond produced by two atoms sharing electrons is called a ____________________ bond.
160. Sodium atoms tend to lose electrons and chlorine atoms tend to gain electrons. When they do, the two kinds of charged atoms attract each other. This is called ____________ bond
161. What charge would you expect to find on a beryllium ion? A chloride ion? Explain.
162. What is meant by a polar molecule? Why is it important that water is a polar molecule?
163.  What is a hydrogen bond?
164.  Why does oxygen have such a low solubility in water?
165. As the temperature increases, the solubility of a solid solute in a liquid solvent usually _______________ (increases, decreases, remains the same)
166. As the temperature increases, the solubility of a gas in a liquid solvent _______________ (increases, decreases, remains the same).
167.  How does soap work?
168. An acid donates ______________________ .
169. When an acid and a base neutralize each other, they form water and a ________________.
170. Is it possible for a substance to behave as an acid in one instance and as a base in another?
171. Why does a solution of a strong acid conduct electricity better than a solution of a weak acid at the same concentration?
172. What does pH measure?
173. You measure the pH of 5 solutions to be 3, 8, 7, 5, and12. Which is the weak acid? The strong acid? The neutral solution? The weak base? The strong base?
174. What causes acid rain?
175. Is the ocean acidic or basic?
176. Give two examples of oxidation-reduction reactions.
177. Which atom has been oxidized in the reaction below?
178. How are corrosion and combustion alike?
179. How are corrosion and combustion different?
180. How does your car battery get charged?
181. Aluminum gives up electrons very easily. Why doesn’t it corrode away the way iron does?
182. Carbon atoms can form a great variety of structures, some of them very complex, because each carbon atom can form ___________ bonds.
183.  How do two structural isomers differ from each other? How are they alike?
184.  What does it mean when we say that a hydrocarbon is unsaturated?
185.  What functional group do all alcohol molecules have?
186. Draw all the structural isomers of a molecule whose formula is C6H14
187. What do all aromatic hydrocarbons have in common?
188. Each of the following devices converts energy from one form to another. For each device, what form of energy is converted into what other form? (a). a motor, (b). a generator, (c). a battery, (d). an engine
189. What is meant by a greenhouse gas?
190. What sources of energy come directly or indirectly from the sun? Are there any that do not?