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SIMULATED PHYSICS ACHIEVEMENT TEST (SAT II) Test # 1 Copyright 1992, 1997 by Edwin R. Schweber Exclusively distributed by physicsweb.com http://www.physicsweb.com

This test may only be used by teachers with their own students at public, religious, or non-profit private institutions. Since this test is being distributed free to publicize the physicsweb.com internet site, you may not distribute this test beyond your own classroom. If you know of other teachers who wish to have a copy of this test, please direct them to http://www.physicsweb.com. Any copies of this test that you distribute to your students must be complete copies that include this cover page and the copyright notices on each of the subsequent pages, but which need not include the answer key on the last page. You may cut and paste individual questions from this test into your own tests. However, if you do so, you may not then distribute those tests to other teachers and you may not represent those tests in any way that would suggest that the questions that you cut and pasted from this document were written by you.

Simulated Physics Achievement Test # 1

Page 1

1. What is the magnitude of the acceleration of a 3 kg object when a net force of 12 newtons acts on it? (A) 12 m/s2 (B) 3.0 m/s2 (C) 36 m/s2 (D) 4.0 m/s2 (E) 0.25 m/s2 2. Which picture below shows the proper way a battery, a resistor, a voltmeter and an ammeter should be wired together in order to experimentally determine the resistance of the resistor? A

A

A

V

V

V





A

V V

A



3. An astronaut whose mass is 50 kilograms on the surface of the Earth discovers that her mass is also 50 kilograms on the surface of planet X. What is the acceleration due to gravity on the surface of planet X? (A) 480 m/s2 (B) 50 m/s2 (C) 5.1 m/s2. (D) 1.0 m/s2 (E) It cannot be determined based on the given information 4. A girl standing 2 meters in front of a plane mirror wishes to take a picture of her reflection. To what object distance should she set her camera lens? (A) 2 meters (B) 1 meter (C) 4 meters (D) 0.5 meters (E) 3 meters

Copyright 1992, 1997 by Edwin R. Schweber

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Simulated Physics Achievement Test # 1

Page 2

5. You would most likely be successful in using the photoelectric effect to charge a previously uncharged electroscope if your light source was (A) sunlight that has been passed through a red filter (B) sunlight that has been passed through a green filter (C) infrared light (D) ultraviolet light (E) a red laser beam 6. An impulse of 15 newton-seconds acts on an object that is initially at rest. What additional information, if any, would you need to be able to find the momentum of this object after the impulse has acted? (A) you have all the information you need (B) only the time interval during which the force was applied (C) only the magnitude of the applied force (D) only the mass of the object (E) both the magnitude of the applied force and the time interval during which it acted 7. The unit newton is equivalent to (A) (kg-m)/s (B) (kg-m)/s2 (C) m/s (D) kg-s (E) m-s Questions 8 and 9 The picture below shows the electric field lines between a segment of a parallel plate capacitor that for all practical purposes extends an infinite distance to the right and to the left. Four points P, Q, R, and S are marked off on this picture. ++++++++++ P Q R S __________

8. At which point is the magnitude of the electric field the largest? (A) point P (B) point Q (C) point R (D) point S (E) the magnitude is the same at all four points 9. At which point is the electric potential the largest? (A) point P (B) point Q (C) point R (D) point S (E) the potential is the same at all four points

Copyright 1992, 1997 by Edwin R. Schweber

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10. An object hanging from a vertical spring is vibrating in simple harmonic motion with a period of 1.2 seconds. If the mass is at its maximum displacement above the equilibrium position, how much time must elapse before it is next at its maximum displacement below the equilibrium position? (A) 2.4 seconds (B) 0.60 seconds (C) 0.30 seconds (D) 1.2 seconds (E) 0.90 seconds 11. What is the magnitude of the momentum of a 3.0 kilogram object moving with a speed of 12 m/s? (A) 4 m/kg-s (B) 36 (kg-m)/s (C) 430 kg-m2/s2 (D) 220 kg-m2/s2 (E) 0.25 (kg-s)/m 12. Which of the following cannot be polarized? (A) sunlight (B) laser light (C) a transverse wave on a string (D) radio waves (E) sound 13. How much work is required to move a 3 coulomb charge through a potential difference of 15 volts? (A) 5 joules (B) 15 joules (C) 45 joules (D) 135 joules (E) 0.33 joules Questions 14 to 18 Select the answer that best completes the word analogy. Note that the analogies in questions 17 and 18 begin the same way, but have different choices. 14. electric field : electric potential :: (A) mass : charge (B) force : potential energy (C) electric currents : resistance (D) potential energy : power (E) electric current : power 15. acceleration : velocity (A) distance : displacement (B) displacement : velocity (C) velocity : displacement (D) displacement : acceleration (E) work : energy 16. watts : horsepower:: (A) kilograms : newtons (B) velocity : acceleration (C) weight : force (D) velocity : speed (E) centimeters : inches Copyright 1992, 1997 by Edwin R. Schweber

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17. impulse : work :: (A) force : acceleration (B) time : distance (C) kinetic energy : potential energy (D) velocity : speed (E) conservative forces : non-conservative forces 18. impulse : work (A) force : velocity (B) Newton's second law : Newton's third law (C) momentum : kinetic energy (D) work : power (E) mechanical energy : heat energy 19. Which of the following is NOT a vector quantity? (A) momentum (B) acceleration (C) force (D) kinetic energy (E) impulse 20. The power consumption of an electric motor is 50 watts. How much total energy is required to operate this motor for two minutes? (A) 50 joules (B) 0.04 joules (C) 100 joules (D) 1.2 joules (E) 6.0 x 103 joules

Question 21

W

100 N

21. The picture above shows a 100 Newton box attached by a string over a massless, frictionless pulley to another box of weight W. If the tension in the connecting string is 120 newtons and the pulley can rotate freely, which of the following statements about W must be correct? (A) W < 100 newtons (B) W > 120 newtons (C) W = 100 newtons (D) W = 120 newtons (E) 100 newtons < W < 120 newtons

Copyright 1992, 1997 by Edwin R. Schweber

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22. Imagine that we define the following new units: The jubjub temperature scale, where the freezing point of water is 25 degrees jubjub and the boiling point of water is 75 degrees jubjub A unit of heat, the brillig, where one brillig is the amount of heat that must be added to one gram of water to raise its temperature by one degree jubjub. What will the specific heat capacity of water be in terms of these new units? (A) 1 brillig per gram per degree jubjub (B) 25 brilligs per gram per degree jubjub (C) 75 brilligs per gram per degree jubjub (D) 50 brilligs per gram per degree jubjub (E) 0.02 brilligs per gram per degree jubjub 23. For which optical device(s) on the list below will the size of the image formed of a real object always be smaller than the size of that object? I. a plane mirror II. a convex lens III. a concave lens (A) III only (B) I and II, only (C) II and III only (D) II only (E) none of these 24. A 20-Newton horizontal force is acting to the right on a 5-kg object which is on a horizontal surface; but the object’s acceleration is only 3 m/s2 to the right. Which of the statements below could best explain this? (A) there is no friction (B) there is a 5 Newton frictional force acting horizontally to the right (C) there is a 5 Newton frictional force acting horizontally to the left (D) this is happening on a planet where the acceleration due to gravity is greater than it is on Earth (E) this is happening in outer space where there is no gravity 25. A physics teacher gives the following example: A student standing on the side of a highway notices that the cars are approaching her at equal time intervals but that when she walks towards the oncoming traffic the time intervals between the cars decreases. Which of the following is the teacher most likely trying to explain? (A) the relationship between frequency, period and wave speed (B) that the pitch of a siren is higher when you are approaching it than when you are stationary. (C) that the pitch of a siren is lower when you are approaching it than when you are stationary (D) that the volume of a siren gets progressively louder as you approach it. (E) that the volume of a siren gets progressively lower as you approach it.

Copyright 1992, 1997 by Edwin R. Schweber

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C D

B A

26. The picture above shows a ball tied to a mass which is being whirled in a vertical circle at a constant speed on the surface of the Earth. At which of the four labeled points on the circle would the tension in the string be the largest? (A) point A (B) point B (C) point C (D) point D (E) the tension would be the same at all four points Question 27

R3 R1 R2 R4

R5

27. In the circuit shown above each of the five resistors has the same resistance. Which resistor will have the greatest potential difference across it? (A) R1 (B) R2 (C) R3 (D) R4 (E) R5 28. A certain light bulb is rated to draw electrical energy at the rate of 100 watts when it is wired across a potential difference of 120 volts. At what rate would the bulb draw energy if it were instead wired across a potential difference of only 60 volts? Neglect any effect that the different temperatures in the different situations may have. (A) 100 watts (B) 200 watts (C) 400 watts (D) 50 watts (E) 25 watts 29. The gravitational force between two spherical masses is 8.0 x 10-11 newtons when their centers are separated by 3.0 meters. What would the force be if their centers were separated by 6.0 meters? (A) 8.0 x 10-11 newtons (B) 16 x 10-11 newtons (C) 4.0 x 10-11 newtons (D) 2.0 x 10-11 newtons (E) 1.0 x 10-11 newtons Copyright 1992, 1997 by Edwin R. Schweber

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Simulated Physics Achievement Test # 1

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30. You are told that both a 3-newton horizontal force and a 4-newton horizontal force are acting on an object, but you are not told their directions. Based only on this information what is the possible range for the magnitude F of the net force acting on the object? (A) 3 ≤ F ≤ 4 (B) 1 ≤ F ≤ 4 (C) 3 ≤ F ≤ 5 (D) 4 ≤ F ≤ 5 (E) 1 ≤ F ≤ 7 Question 31

Radio

31. The picture above shows an electric circuit with a radio, five switches, three resistors and a battery. All five of the switches are open so that no current can flow through them. What is the least number of switches that must be closed for there to be a current through the radio? (A) one switch (B) two switches (C) three switches (D) four switches (E) five switches 32. A teacher has two long combs whose teeth are separated by very slightly different amounts. She lines up one comb directly behind the other and shows that as you look along the combs in some places a tooth of one comb is directly behind a tooth of the other comb and that in other places the tooth of one comb is behind a space in the other comb. The teacher is most likely trying to explain (A) beats (B) Doppler shift (C) Huygen's principle (D) refraction (E) diffraction 33. A 60-kg and a 30-kg ice skater face each other on a frictionless ice pond. They are initially at rest and then push off against each other. If the 60-kg skater has a final speed of 4 m/s, what would the speed of the 30-kg skater be? (A) 4 m/s (B) 2 m/s (C) 8 m/s (D) 1 m/s (E) 16 m/s

Copyright 1992, 1997 by Edwin R. Schweber

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Page 8

3Ω 6Ω 3Ω 34. In the circuit above consisting of a battery and three resistors a current I flows through the battery. If the combination of the three individual resistors were to be replaced by a single resistor, what resistance must that single resistor have so that the same current I will still flow through the battery? (A) 12 ohms (B) 7.5 ohms (C) 1.2 ohms (D) 3 ohms (E) 6 ohms 35. A hammer and a feather simultaneously dropped near the surface of the Earth will not keep up with each other as they fall. However, if this experiment were to be performed on the surface of the Moon, the hammer and the feather would keep up with each other. This is best explained by the fact that (A) the air on the Moon is much denser than it is on the Earth (B) there is no air on the Moon (C) the Moon has no gravity (D) the Moon has gravity, but it is much weaker than on the Earth (E) the gravity on the Moon is much stronger than it is on the Earth 36. A 10 kg. satellite requires a speed of 8,000 m/s to stay in a circular orbit at a certain height above the Earth. What speed would be required to keep a 5 kg. satellite in the same orbit? (A) 2,000 m/s (B) 4,000 m/s (C) 8,000 m/s (D) 16,000 m/s (E) 32,000 m/s 37. A book is at rest on a table. What is the Newton’s third law reaction force to the weight of the book? (A) the upward force of the table on the book (B) the downward force of the book on the table (C) the downward pull of the Earth on the book (D) the upward pull of the book on the Earth (E) the friction between the table and the book

Copyright 1992, 1997 by Edwin R. Schweber

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Page 9

t1

time

t2

I

accel.

accel.

accel.

Question 38

t1

time

t2

II

t1

t

time 2

III

38. An object is travelling in the positive direction along a straight line path at time t1. Each of the three graphs above shows possible ways the acceleration of this object could change between time t1 and time t2. For which graph(s) will the object's speed be increasing throughout the entire time interval from t1 to t2? (A) graph I only (B) graph II only (C) graph III only (D) graphs I and II only (E) graphs I, II and III 39. An 25 year old astronaut is blasting off for a lengthy high speed voyage while her identical twin remains on Earth. Which of the following will most likely be the situation when the astronaut returns to the Earth? (A) both twins will be 70 years old (B) the astronaut will be 25 years old and her twin will be 50 years old (C) both twins will be 30 years old while everyone else on Earth has aged by 10 years (D) the earthbound twin will be 25 years old while her astronaut sister is 50 years old (E) both twins will be 35 years old while everyone else on the Earth has aged by only 5 years Question 40

electron

40. The picture above shows the path of a moving electron. Which of the following could be a reason why the electron is following this specific path rather than moving in a straight line? (A) there is a magnetic field pointing perpendicularly into the page (B) there is an electric field pointing perpendicularly into the page (C) there is an electric field pointing towards the left (D) there is a magnetic field pointing perpendicularly out of the page (E) there is an electric field pointing perpendicularly out of the page

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41. Which optical device(s) on the list below will always form a virtual image of a real object regardless of how far the object is away from the device? I. plane mirror II. convex lens III. concave lens (A) I and III, only (B) I, II, and III (C) none of them (D) II and III, only (E) I and II, only 42. Which of the following would have the greatest effect on the period of a simple pendulum made by tying a spherical object to one end of a string? (A) moving the pendulum from a laboratory table to the floor (B) changing the maximum angle through which the pendulum swings with respect to the vertical from 5 degrees to 7 degrees (C) changing the length of the string from 10 cm. to 20 cm. (D) changing the mass of the spherical object from 100 grams to 200 grams (E) changing the spherical object from 100 grams of iron to 100 grams of lead 43. When monochromatic light is passed through a double slit diffraction grating with a screen behind it, the first order maximum on the screen will be at a point where the difference in the distance from that point to each slit is equal to (A) one-quarter of the wavelength of the light (B) one-half of the wavelength of the light (C) one wavelength of the light (D) two wavelengths of the light (E) four wavelengths of the light 44. A renegade elephant escapes from a circus into an elevator where it starts pushing the buttons at random with its trunk. The elephant's weight is only slightly less than the maximum tension the elevator's cable can withstand without breaking. In which of the following situations will there be the greatest risk that the cable will break? (A) the elevator remains stationary (B) the elevator accelerates upward (C) the elevator accelerates downward (D) the elevator moves upward at a steady speed (E) the elevator moves downward at a steady speed 45. An unoccupied sled is sliding towards a boy on a horizontal, frictionless ice pond. The sled has a mass of 10 kg. and a speed of 6 m/s. The boy is just able to stop the sled by throwing a 2 kg. rock at it. With what momentum will the boy recoil? (A) you need to know the speed of the rock to answer this question (B) 12 (kg-m)/s (C) 60 (kg-m)/s (D) 30 (kg-m)/s (E) 20 (kg-m)/s

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46. A kicked football follows a parabolic path until it once again hits the ground. Which of the following statements about the football over the course of its trajectory is (are) true? I. The vertical component of the football’s velocity is zero at the highest point of its trajectory II. The kinetic energy of the football is zero at the highest point of its trajectory. III. The sum of the kinetic and potential energy of the football is the same everywhere along its trajectory (A) I and II only (B) II and III only (C) I and III only (D) I only (E) I, II and III 47. You wish to design an ammeter and a voltmeter so that when they are properly wired into a circuit they will have the least effect on the properties of the circuit being tested. What needs to be true about the resistance of the voltmeter and the ammeter? (A) neither resistance will have an effect on the circuit (B) both the voltmeter and the ammeter should have a low resistance (C) both the voltmeter and the ammeter should have a high resistance (D) the ammeter should have a high resistance and the voltmeter should have a low resistance (E) the ammeter should have a low resistance and the voltmeter should have a high resistance

Epsilon

Delta

Gamma

Beta

Alpha

Question 48

48. The cities of Alpha, Beta, Gamma Delta, and Epsilon all lie along a straight East-West road as shown on the map above. An airplane is flying at a constant velocity due East directly over this road. When the plane is directly over Beta, a screw falls off. The plane continues to fly due East at the same constant velocity that it had been maintaining. The plane itself is directly over Delta when the screw hits the ground. Neglecting air friction, the screw will land closest to the city of (A) Alpha (B) Beta (C) Gamma (D) Delta (E) Epsilon

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Page 12

velocity (m/s)

Questions 49 to 51 Base your answers to questions 49 to 51 on the graph below. The graph shows the velocity as a function of time for an object that was originally at rest until at time t = 0 seconds it began to move in the positive direction along a straight line path.

10 0 -5

9 3

12

time (s)

6

-10

49. At what time after t = 0 seconds will the object first return to its position at t = 0 seconds? (A) 3 seconds (B) 6 seconds (C) 9 seconds (D) 12 seconds (E) sometime after 12 seconds 50. At what time after t = 0 seconds does the object first begin to reduce its speed? (A) 0 seconds (B) 3 seconds (C) 6 seconds (D) 9 seconds (E) 12 seconds 51. At what time after t = 0 seconds does the object first begin to travel southward? (A) 3 seconds (B) 6 seconds (C) 9 seconds (D) 12 seconds (E) the object never travels southward during the time interval shown

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52. Each of the pictures below shows four objects tied together with rubber bands being pulled to the right across a horizontal frictionless surface by a horizontal force F. All the objects have the same mass; all rubber bands obey Hooke's law, have the same equilibrium length, and the same force constant. Which of these pictures is drawn most correctly

F

F

F

F

F

Question 53

I

II 4µ C

III -12 µ C

53. The picture above shows a positive and a negative electric charge and a line drawn through these charges. This line is divided into three segments. In which segment(s) would it be possible to find a point where a third positive charge could be placed without this third charge experiencing a net force due to the first two charges? (A) segment I, only (B) segments I and III, only (C) segments I, II and III (D) segment II, only (E) segment III only

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Question 54

100 g 100 o

100 g 0o

54. The picture above shows two well insulated cups, each filled with 100 grams of water, and an un-insulated U-shaped metal bar that extends between them. The water in one cup is at an initial temperature of 100 oC and the water in the other cup is at an initial temperature of 0 oC. Heat flows through the metal bar until the water in each cup reaches the same equilibrium temperature. If some, but not all, of the heat flowing through the bar escapes into the surrounding air, whose temperature is 25 oC, which of the following would most likely be the temperature of the water in each cup when the temperatures first become the same? (A) 10 oC (B) 25 oC (C) 40 oC (D) 50 oC (E) 75 oC 55. A teacher places two small loudspeakers about 50 centimeters apart on a desk in front of his classroom. Each speaker is emitting sound with the same frequency and with the same intensity. The students are asked to slowly walk past the desk. As they do so, they hear alternate soft and loud sounds. This is best explained by (A) refraction (B) diffraction (C) reflection (D) wave interference (E) polarization

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temperature

Question 56

time The graph at the right shows temperature versus time of a certain substance which was originally a solid as heat was added to it a constant rate until it became a liquid and eventually a vapor. Since the graph does not have a numerical scale it is impossible to obtain numerical answers from it. However, given the overall shape of the graph only one of the lines in the chart below could possibly be correct. Which line is it?

(A) (B) (C) (D) (E)

Sp. Heat solid (cal/g-oC)

SpHeat liquid (cal/g-oC)

Sp.Heat gas (cal/g-oC)

0.7 0.8 0.5 0.2 0.2

0.7 0.4 1.0 0.4 0.4

0.7 0.2 0.5 0.8 0.8

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LatentHeat of fusion (cal./g) 40 70 80 70 35

Latent Heart of vaporization (cal./g) 40 35 540 35 70

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57. The picture below shows a track which is part of a vertical circle. If a ball is released from rest at the left end of the track, which of the dotted lines best shows the trajectory that it would follow after it leaves the right end of the track?







58. Each of the pictures below shows two parallel current carrying wires. The arrows show the direction of the conventional current. For which picture(s) will the magnetic field be pointing perpendicularly into the page at every point between the wires?

I

II

III

(A) pictures I, II, and III (B) picture II, only (C) picture III, only (D) pictures II and III, only (E) picture I, only

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Questions 59 to 61 An interplanetary exchange student studying at an Earthling high school has been given a physics problem asking about the height at which a soccer ball hits a wall downfield from where the ball was kicked. The exchange student’s answer, given below, is almost perfectly correct except that she has mistakenly used the value for the acceleration of gravity on her native planet rather than the value on Earth and that she has omitted the units in some of her steps. o

Vy = 10 sin 30 o = 5 Vx = 10 cos 30 = 8.7 7 = 8.7t t = 0.8 y = 5(0.8) - (1/2)(6)(0.8)2 = 2.1 meters 59. Based on this solution, what was the speed of the ball immediately after it was kicked? (A) 10 m/s (B) 5 m/s (C) 8.7 m/s (D) 13.7 m/s (E) 6 m/s 60. Based on this solution, what was the horizontal distance between the kicker and the wall? (A) 10 meters (B) 6 meters (C) 0.8 meters (D) 7 meters (E) 8.7 meters 61. Based on this solution, what is the acceleration due to gravity on the surface of the student’s native planet? Remember that the student mistakenly used this value rather than the value here on Earth. (A) 9.8 m/s2 (B) 3 m/s2 (C) 6 m/s2 (D) 7 m/s2 (E) 8.7 m/s2

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62. One of the three graphs below shows displacement versus time for a certain object, another shows velocity versus time for that same object and the third shows acceleration versus time for that object.

I

II

III

Which line in the chart below correctly indicates which graph is which? Disp. vs. Time (A) (B) (C) (D) (E)

Vel. vs. Time

graph III graph II graph I graph II graph III

graph II graph I graph II graph III graph I

Accel. vs. Time graph I graph II graph III graph I graph II

timer

Question 63

tape

` 63. The picture above shows the setup for an experiment. The cart on the left is to be rolled into a stationary cart on the right. Both carts have the same mass. There is a wad of clay at the end of the carts so that they will stick together after the collision. A thin strip of paper tape is attached to the left end of the left cart and is run through a device that will make a dot on the tape at regular intervals both before and after the collision. Which picture below best shows what the pattern of dots on the tape will look like after the experiment is performed? In each picture the tape is oriented so that dots toward the left were the ones made before the collision. Notice that vertical grid lines have been drawn to help you judge the distance between the dots.





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Question 64:

Q Q Q 64. The picture above shows a perpendicular axis system and three positive charges, all with the same magnitude Q. One charge is at the origin, one charge is on the y-axis, and one charge is on the x-axis. The two charges on the axes are the same distance from the origin. Which picture below best shows the direction of the net force that would be exerted on the charge at the origin due to the other two charges?

The force is zero and has no direction





65. A 4 kg. cart is rolling to the right with a speed of 3 m/s when a force acting to the right does 18 joules of work on it. What is the kinetic energy of the cart after this work is performed? (A) 18 joules (B) zero joules (C) 36 joules (D) 54 joules (E) 30 joules 10

20

30

40

50

60

70

80

90

8N

66. As shown in the picture above, a uniform meter stick in rotational equilibrium is supported by a pivot at the 70 centimeter mark while an 8 newton weight hangs from it at the 80 centimeter mark. What is the weight of the meter stick? (A) 8 newtons (B) 4 newtons (C) 16 newtons (D) 32 newtons (E) 2 newtons

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Question 67:





67. The picture above shows three objects: Object A, a circular disk; object B, a square frame; and object C, a square sheet. All three objects have the same mass and uniform densities. The dimensions indicated by an arrow in each of the pictures are the same. The moments of inertia about axes perpendicular to the planes of the objects through their center points are IA, IB, and IC. Which choice below makes a correct comparison between the three moments of inertia? (A) IC > IA > IB (B) IC = IB > IA (C) IC = IA > IB (D) IB > IC > IA (E) IA = IB = IC 68. A record turntable is rotating freely (the motor is not running). Which of the following would be true if a small insect which was originally at rest with respect to the turntable on its outer edge walks halfway towards the center and once again comes to rest with respect to the turntable. I. The combined kinetic energy of the turntable and the insect will increase. II. The combined angular momentum of the turntable and the insect will increase. III. The combined kinetic energy of the turntable and the insect will remain the same. IV. The combined angular momentum of the turntable and the insect will remain the same. (A) I and IV, only (B) II and III, only (C) I and II, only (D) III and IV, only (E) III, only 69. Which of the following situations involving heat engines could not occur according to the Second Law of Thermodynamics? I. For every 100 joules of heat that flow into the engine the engine performs 100 joules of work. II. For every 100 joules of heat that flow into the engine the engine performs 50 joules of work III. For every 100 joules of heat that flow into the engine the engine performs 200 joules of work (A) II, only (B) III, only (C) I, II and III (D) I and III, only (E) II and III only Copyright 1992, 1997 by Edwin R. Schweber

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Simulated Physics Achievement Test # 1

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70. A teacher gives her students the following test problem: Box A which is sliding to the right along a frictionless horizontal surface collides with box B which was initially at rest. The two boxes stick together after the collision and continue sliding as a single unit. Find the final speed of the combined boxes. However, rather than giving the students the necessary information, the teacher is making them purchase the information according to the following price list. The change in the kinetic energy of box B as a result of the collision The change in the momentum of box B as a result of the collision The average force acting on box B during the collision The time that the two boxes are in contact while they are colliding The mass of box B

$5 $8 $7 $9 $4

What is the least amount of money that must be spent in order to purchase enough information to solve the problem? (A) $9 (B) $16 (C) $12 (D) $15 (E) $14

71. A standing wave with a 36 centimeter wavelength is established along a horizontal string. If point P on this string is an antinode, what is the horizontal distance between point P and the closest node? (A) 36 cm (B) 72 cm (C) 18 cm (D) 27 cm (E) 9 cm 72. Each of the graphs below shows the potential difference, ∆V, across an electrical device versus the current, I, that is flowing through it. Which graph represents a device for which Ohm's Law is true?

∆V

∆V

∆V

I

I

Copyright 1992, 1997 by Edwin R. Schweber

∆V I

∆V

I

I



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Simulated Physics Achievement Test # 1

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73. A tuning fork vibrating at 300 Hz is held close to a second tuning fork for a brief interval before being removed. Following this, the second tuning fork will most likely be vibrating with the greatest amplitude if its own natural frequency of vibration is (A) 150 Hz (B) 300 Hz (C) 310 Hz. (D) 600 Hz (E) 290 Hz 74. A transverse wave is passing through a horizontal string. The first picture below shows the shape of the string at an instant of time. This picture is superimposed on an axis system to help you make any necessary measurements. The second picture below is a graph of the vertical displacement of one point along the string as a function of time

4

centimeters

3 2 1 0 -1 0

2

4

6

8 10 12 14 16 18 20 22 24 26 28 30 32 34 36

-2 -3 -4

centimeters

centimeters

4 3 2 1 0 -1 0 -2 -3 -4

1

2

3

4

5

6

7

8

9

seconds

How far does this wave travel along the string in one second? (A) 0.3 cm (B) 3 cm (C) 9 cm (D) 27 cm (E) 36 cm

Copyright 1992, 1997 by Edwin R. Schweber

For related internet resources: http://www.physicsweb.com

Simulated Physics Achievement Test # 1

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Question 75

S N







current current current current current

75. The picture above shows a magnet attached to a spring and an adjacent electrical circuit consisting of a resistor connected to a coil of wire wrapped around a hollow cardboard core. If the magnet were to be set into simple harmonic motion with a small amplitude, which graph below best shows how the induced current in the coil would vary as a function of time? The sign convention being followed is that positive currents are flowing through the resistor to the right and that negative currents are flowing through the resistor to the left.

time

time

time

time

Copyright 1992, 1997 by Edwin R. Schweber

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Simulated Physics Achievement Test # 1

Page 24

SIMULATED ACHIEVEMENT TEST #1 ANSWER KEY 1) D 2) D 3) E 4) C 5) D

26) A 27) A 28) E 29) D 30) E

51) B 52) B 53) A 54) C 55) D

6) A 7) B 8) E 9) A 10) B

31) B 32) A 33) C 34) D 35) B

56) D 57) C 58) B 59) A 60) D

11) B 12) E 13) C 14) B 15) C

36) C 37) D 38) E 39) B 40) D

61) C 62) D 63) D 64) C 65) C

16) E 17) B 18) C 19) D 20) E

41) A 42) C 43) C 44) B 45) C

66) B 67) D 68) A 69) D 70) A

21) B 22) A 23) A 24) C 25) B

46) C 47) E 48) D 49) E 50) B

71) E 72) C 73) B 74) B 75) C

Copyright 1992, 1997 by Edwin R. Schweber

For related internet resources: http://www.physicsweb.com