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Sample
Exam Name___________________________________ MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The figure below shows the position of a particle (moving along a straight line) as a function of time. Which of the following statements is true? 1) A) The object is accelerating (speeding up). B) The object is moving at a constant velocity. C) The object is deaccelerating (slowing down). Answer: C Explanation: A) B) C) 2) An object has a velocity directed to the right, and an acceleration directed to the left. Which statement is true? A) The position of the object is not changing in time. B) The position of the object is increasing to the right with time, and its speed is increasing. C) The position of the object is increasing to the left with time, and its speed is increasing. D) The position of the object is increasing to the right with time, and its speed is decreasing. Answer: D Explanation: 2) A) B) C) D) SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 3) A possible unit for the measure of time would be the period of your own pulse. Why might this unit not be a good choice for a time standard? Answer: In general, the human pulse rate often changes. Also, other people would in general, have different pulse rates, so it would be difficult to reproduce the standard. Explanation: 1 3) 4) If you needed to estimate the number of gallons of gasoline burned in the United States each year by automobiles, what quantities would you need to assume? What formula would you need to use? 4) Answer: If you assumed N = total number of cars M = Average number of miles driven each year per car R = Average number of miles per gallon Then Total number of gallons = N ·M R Explanation: 5) The length of a certain piece of wood is stated as 12.946 cm. Thinking in terms of accuracy and significant figures, what value would you obtain if you measured this board with a ruler whose smallest division is the millimeter? 5) Answer: Since 1 cm = 10 mm, you could only measure this board to 1/10 of a centimeter, therefore, 12.9 cm. Explanation: 6) What are some advantages of using scientific notation to express very large or very small numbers? 6) Answer: The main advantage is the ability to express these numbers in a minimum amount of space. For example, 1 trillion = 1,000,000,000,000 = 1 × 1012 . Explanation: MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 7) The radius of a rotating turntable is 2.2 m. If it turns through an angle of 1.1 radians, through what distance does a point on the edge move? A) 2 m B) 2.4 m C) 0.5 m D) 10 m Answer: B Explanation: A) B) C) D) 8) A record player turns through an angle of 4.50 radians. How many degrees does it turn through? A) 198° B) 258° C) 129° D) 108° Answer: B Explanation: 7) A) B) C) D) 2 8) 9) What is 0.2052/3, to the proper number of significant figures? A) 0.3477 B) 0.348 C) 0.35 Answer: B Explanation: D) 0.3 A) B) C) D) 10) Estimate the number of times an average person's heart beats in a lifetime. Assume the average heart rate is 73 beats/min and a life span of 74 yr. A) 3 × 108 beats B) 3 × 1010 beats C) 3 × 107 beats D) 3 × 109 beats Answer: D Explanation: D) 1.71 × 106 mg 13) A) B) C) D) 14) A marathon is 26 mi and 385 yd long. Estimate how many strides would be required to run a marathon. Assume a reasonable value for the average number of feet/stride. A) 4.5 × 104 strides B) 4.5 × 103 strides C) 4.5 × 106 strides D) 4.5 × 105 strides Answer: A Explanation: 12) A) B) C) D) 13) A weight lifter can bench press 171 kg. How many milligrams (mg) is this? A) 1.71 × 107 mg B) 1.71 × 108 mg C) 1.71 × 109 mg Answer: B Explanation: 11) A) B) C) D) 12) A plot of land contains 5.8 acres. How many square meters does it contain? [1 acre = 43,560 ft2 ]. A) 7.1 × 103 m2 B) 5.0 × 104 m2 C) 2.3 × 104 m2 D) 7.0 × 104 m2 Answer: C Explanation: 10) A) B) C) D) 11) An oak tree was planted 22 years ago. How many seconds does this correspond to? (Do not take leap days into account.) A) 2.8 × 108 B) 6.9 × 108 C) 2.9 × 107 D) 1.2 × 107 Answer: B Explanation: 9) A) B) C) D) 3 14) 15) A CD-ROM disk can store approximately 600.0 megabytes of information. If an average word requires 9.0 bytes of storage, how many words can be stored on one disk? A) 5.4 × 109 words B) 2.0 × 109 words C) 2.1 × 107 words D) 6.7 × 107 words Answer: D Explanation: A) B) C) D) 16) A person on a diet loses 1.6 kg in a week. How many micrograms/second (µg/s) are lost? A) 1.6 × 105 µg/s B) 6.4 × 104 µg/s C) 2.6 × 103 µg/s D) 44 µg/s Answer: C Explanation: 16) A) B) C) D) 17) A car is travelling at 46.0 mi/hr. How many meters/second does the car cover? A) 12.9 m/s B) 20.6 m/s C) 48.8 m/s Answer: B Explanation: 15) D) 32.2 m/s 17) A) B) C) D) 18) An equation that you will use later is x = 1 2 at , where a has units of acceleration, t has units of time, 2 18) and x has units of distance. If t = 61.9 s, find the difference between the values of x obtained when a = 9.81 m/s2 and when a = 10.0 m/s2 . A) 4 × 102 m Answer: A Explanation: B) 1 × 103 m C) 6 × 102 m D) 3 × 102 m A) B) C) D) 19) Which of the following is a reasonable estimate of the number of characters (typed letters or numbers) in a 858 page book? Assume an average of 163 words/page and a reasonable average number of letters/word. A) 6 × 105 char B) 6 × 106 C) 6 × 104 char D) 6 × 107 char Answer: A Explanation: A) B) C) D) 4 19) 20) The wavelength of a certain laser is 0.35 micrometers, where 1 micrometer = 1 × 10-6 m. What is this wavelength in nanometers? A) 3.5 × 101 nm B) 3.5 × 102 nm C) 3.5 × 104 nm D) 3.5 × 103 nm Answer: B Explanation: 21) What is A) B) C) D) 0.674 to the proper number of significant figures? 0.74 A) 0.91 Answer: A Explanation: B) 0.9 C) 0.911 C) 4.8 × 10-4 D) 12.8 km/L 22) D) 2.1 × 103 23) A) B) C) D) 24) Add 3685 g and 66.8 kg and express your answer in milligrams (mg). A) 7.05 × 107 mg B) 7.05 × 105 mg C) 7.05 × 104 mg Answer: A Explanation: D) 0.9108 A) B) C) D) 23) Express [4.3 × 106 ]-1/2 in scientific notation. A) 2.1 × 10-5 B) 2.1 × 104 Answer: C Explanation: 21) A) B) C) D) 22) Your car gets 30.2 mi/gal on a trip. How many kilometers/liter did it get? A) 28.2 km/L B) 48.6 km/L C) 7.97 km/L Answer: D Explanation: 20) A) B) C) D) 5 D) 7.05 × 106 mg 24) 25) How many nanoseconds does it take for a computer to perform one calculation if it performs calculations 6.7 × 107 ? second A) 67 ns Answer: C Explanation: B) 65 ns C) 15 ns 25) D) 11 ns A) B) C) D) TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. 26) If a vector pointing to the right has a positive magnitude, then one pointing to the left has a negative magnitude. Answer: True Explanation: False 27) If successive images of an object in a motion diagram get closer and closer together, then that object is accelerating. Answer: True Explanation: 32) False 33) If an object has a changing speed, its velocity must also be changing; but if it has a changing velocity, its speed is not necessarily changing. Answer: True Explanation: 31) False 32) All objects moving in a circle are accelerated. Answer: True Explanation: 30) False 31) Since vectors always have positive magnitudes, the sum of two vectors must have a magnitude greater than the magnitude of either one of them. Answer: True Explanation: 29) False 30) If the average speed of an object is zero, then its average velocity must be zero; but if its average velocity is zero, its average speed is not necessarily zero. Answer: True Explanation: 28) False 29) The change in the position vector of a moving object is equal to the distance it has moved. Answer: True Explanation: 27) False 28) If the final position vector of a moving object has a smaller magnitude than the initial position vector, then the change in the object's position vector has a positive magnitude. Answer: True Explanation: 26) False 6 33) 34) If an object is accelerating toward a point, then it must be getting closer and closer to that point. Answer: True Explanation: False 7 34) Answer Key Testname: C1 1) C 2) D 3) In general, the human pulse rate often changes. Also, other people would in general, have different pulse rates, so it would be difficult to reproduce the standard. 4) If you assumed N = total number of cars M = Average number of miles driven each year per car R = Average number of miles per gallon Then Total number of gallons = N ·M R 5) Since 1 cm = 10 mm, you could only measure this board to 1/10 of a centimeter, therefore, 12.9 cm. 6) The main advantage is the ability to express these numbers in a minimum amount of space. For example, 1 trillion = 1,000,000,000,000 = 1 × 1012 . 7) 8) 9) 10) 11) 12) 13) 14) 15) 16) 17) 18) 19) 20) 21) 22) 23) 24) 25) 26) 27) 28) 29) 30) 31) 32) 33) 34) B B B D B C B A D C B A A B A D C A C FALSE TRUE TRUE FALSE TRUE FALSE TRUE TRUE FALSE 8