Name: PHYS 110 Dr. McGovern Spring 2018 Exam 1. Multiple Choice: Circle the answer that best evaluates the statement or completes the statement.

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1 Name: PHYS 110 Dr. McGoern Sprng 018 Exam 1 Multple Choce: Crcle the answer that best ealuates the statement or completes the statement. #1 - I the acceleraton o an object s negate, the object must be slowng down. A. True B. False # - Suppose that a car traelng to the west (the -x drecton) begns to slow down as t approaches a trac lght. Whch statement concernng ts moton n the x drecton s correct? A. Both ts acceleraton and ts elocty are poste. B. Both ts acceleraton and ts elocty are negate. C. Its acceleraton s poste but ts elocty s negate. D. Its acceleraton s negate but ts elocty s poste. #3 - An object has a elocty drected to the rght, and an acceleraton drected to the let. Whch statement s true? A. The poston o the object s ncreasng to the rght wth tme, and ts speed s ncreasng. B. The poston o the object s ncreasng to the rght wth tme, and ts speed s decreasng. C. The poston o the object s ncreasng to the let wth tme, and ts speed s ncreasng. D. The poston o the object s not changng n tme. #4 - The moton o a partcle s descrbed n the elocty ersus tme graph shown n the gure. We can say that ts speed A. ncreases the entre tme. B. decreases the entre tme. C. ncreases and then decreases. D. decreases and then ncreases. #5 - A ball s thrown drectly upward and experences no ar resstance. Whch one o the ollowng statements about ts moton s correct? A. The acceleraton o the ball s upward whle t s traelng up and downward whle t s traelng down. B. The acceleraton o the ball s downward whle t s traelng up and upward whle t s traelng down. C. The acceleraton s downward durng the entre tme the ball s n the ar. D. The acceleraton o the ball s downward whle t s traelng up and downward whle t s traelng down but s zero at the hghest pont when the ball stops.

2 Instructons: For each o the ollowng problems, present your soluton n the space proded showng all releant work. Be neat and concse. Partal credt can be awarded or answers that are partal correct. Howeer, answers that are messy, dsorganzed, and/or contan an excesse amounts o nonsense wll be penalzed or not graded at all. #6 - You walk 55 meters to the north, then turn 60 to your rght and walk another 45 meters. What s your net dsplacement? State your answer as a magntude and drecton. #7 The gure shows the poston o an object as a uncton o tme, wth all numbers accurate to two sgncant gures. a. What s the total dstance traeled? b. What s the net dsplacement? c. Aerage speed or the entre trp. d. What s the speed at 7 seconds?

3 #8 The gure shows a graph o the elocty as a uncton o tme or a basketball player traelng up and down the court n a straght-lne path. Agan, all numbers accurate to two sgncant gures. a. Draw an acceleraton graph oer the same perod o tme. b. What s dsplacement o the player ater 4 seconds? c. Does the player eer turn around? I so, when? #9 A runner mantans constant acceleraton ater startng rom rest as she runs a dstance o 60.0 m. The runner's speed at the end o the 60.0 m s 8.00 m/s. Aterwards, the runner moes at that top speed or another 6.00 seconds. a. Draw a complete moton dagram o the runner. b. How much tme dd t take the runner to complete the 60.0 m dstance? c. What was the total dstance traeled?

4 #10 A ball s projected upward at tme t = 0.00 s, rom a pont on a roo 90.0 m aboe the ground. The ball rses, then alls and strkes the ground. The ntal elocty o the ball s 36. m/s. Ar resstance s neglgble. a. What s the speed o the ball just beore t strkes the ground? b. How long s the ball n the ar? #11 What s the maxmum dstance we can shoot a dart, rom ground leel, proded our toy dart gun ges a maxmum ntal elocty o.78 m/s and ar resstance s neglgble? Also, calculate how long the dart s n the ar?

5 #1 - A rock s thrown at a wndow that s located 18.0 m aboe the ground. The rock s thrown at an angle o 40.0 aboe horzontal. The rock s thrown rom a heght o.00 m aboe the ground wth a speed o 30.0 m/s and experences no apprecable ar resstance. I the rock strkes the wndow on ts upward trajectory, rom what horzontal dstance rom the wndow was t released? #13 - A partcle mong along the x-axs has ts poston descrbed by the uncton x = 5t - t + 3 m, where t s n seconds. At t = 3s what are the partcle s poston, elocty, and acceleraton? Knematcs s s a t t a s 1 a t Projectle Moton Range = sn( ) g Max Heght = ) sn ( g Flght Tme = sn( ) g