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Unformatted text preview: Mb February 24, 2011
Prof. S. M. Bhagat PHYS 121 EXAM I Name: SAL N (Sign in ink, print in pencil) Notes 1) There are six (6) problems in this exam. Please make sure that your copy has all of
them. 2) Please ShOW your work indicating clearly what formula you used and what the symbols mean. Just writing the answer will not get you full credit.‘ In stating vectors
give both magnitude and direction. < 3) Write your answers on the sheets provided. 4) Do not forget to write the units. 5) ' Do not hesitate to ask for clariﬁcation at any time during the exam. You may ‘buy a
formula at the cost of one point. ' ' Best of Luck! God Bless You! Problem 1 You start from home along a straight road (xaxis) at 30 mph. After 40
minutes, you run out of gas. To reach a gas station you walk back 3 km in 45 minutes. What is your (i) average speed, (ii) average velocity by the time you return to your car?
Why? [Assume 1 mile = 1.61km], 30mph: 3w v A c r lot/grL/W/g. (6,10) 3506)
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(i) Why does it stop rising?
(ii) What is its acceleration at y = 10111?
(iii) What was the initial velocity?
(iv) How long before it returns to ground?
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 Spring '10
 Shawhan
 Physics

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