l,="y Na UNIT lll: Worksheet 3 1 E x I --J 25 I I I I ---¡ I I I I I I I --l I I --T I I ---l I I I I I I I I I I ---t I I - - -r-I - - -rI I I I I I I I I I I I I I I I I I I I -r-I I I I ¡ I I I I --t ---l I I I ---r I I -r- - - - -r-I - - I I I I I 0 a. I I I I I I I I t (s) 5 Describe in words the motion of the object from 0 - 6.0 {,r. 5*or{,'o..rory L se.o.ds, s. Po:o\,'Ye cons\c¡¡\ Y.lou\ of f'5 ^46 Fo- \-t, neÄ* L[ Se co rcl5 o. Construct a qualitative motion map to describe the motion of the object depicted in the graph above. : ù ' ) "* r---''-) 'r* -) -.! Whaì is the instantaneous velocity of the object at the following times? c. i. t:1.0, þ*/S ii. t:3.0, l, S ry/ S \ d. 3,íus \ What is the simple average of these two velocities? What is the average velocity for the entire interval? TWhy are these two values different? ( --, \ \t\0_ v C or, [c..,r [or,t" aâ 2,5 rlls cç¡ = l,s ryf L d+ 1, s = 7.5' ,t^4 -l cl,l{'"'er+ yqtues lre.q,as. on¿ J,.ns\ ùuwc\rt's 1 l^" Ve [o c ,åI L c-a "q ^{., z J,ÀQr^t s{o,*.s ù\ r*tr},!n ca¡r\ e c,s,ly b¿ drrc',b"r/ b¡ onty I f\u rvt b *ts r Or @Modeling Workshop Project 2002 t Z [ Unit III ws3 v2.0 uX*n{,r" Graphically represent the relationship between velocity and time for the object described above. e Ø E I - - JI I - - I t tt rá tttt rttt tttt tttl I I I I I I - - JI I I tttt ¡ - - -L - - J- - - r ttll tttt ttl¡ I I ---L--- I I I I I I .l I ¡ - - F L I I I r a I I I I I I I I L I ¡ ¡ 0 f. tL3q,5b From your velocity vs. time graph determine the total displacement of the object. \/ A.-b¡\a:Þu P A -- 1,5 A' 4ø= v 2. t (s) ct: 3On -+ Ço óX= /'l î- -L?";uL q4 : The graph below represents the position of an object. 3On X B c t D G F a. At what point(s) on the graph above is the object moving most slowly? (How do you know?) b,F b. Over what intervals on the graph above is the object speeding up? (How do you know?) ß-c c r F-(, Over what intervals on the graph above is the object slowing down? (How do you know?) A,\èt tr-F d. At what poin(s) on the graph above is the object changing direction? (How do you know?) [b+F @Modeling Workshop Project 2002 2 Unit III ws3 v2.0 3 . A stunt car driver testing the use of air bags drives a car at a constant speed of 25 m/s for a total of I 00. m. He applies his brakes and accelerates uniformly to a stop just as he reaches a wall 50. m away. a. E Sketch qualitative position vs. time and velocity vs time graphs. UJ 't. l¡ .tu-- J---l itr rll itr itr ¡l¡ ---L - - J-- I I I I I I I I --rI I I I tt tt tt I I tt tt 'L.5 I I t_ I I I I itr rll l--r---. E - -- ¡ ! L ¡ll - - -'- - - - ¡---L ttt ttt - - J- - - ¡ - - -L - ttr ttt ttl tt tl rln n ,,,J",.,,t,.,,. I I n t {s} ,lo TI ü I I I I I ¡ I I t I I - -F ttl ttt _ _ -r_ - - ! - - -r- - ttt ttt ttt J.,,, .,,. ),,,,,t,,,,, -r-I I I I I I __l I _--L--I I - - -rttt - - - - -r- - - I I I- - -r-tl - - -r- - - b. ttl ttl - - - I I I t (s) How long does it take for the car to travel the first 100.m? ôX v-. + ì- ¿\Y- \Ðùrq v L5 1 ''."^',\ 4s r,n c. Remember that the area under a velocity u, tirn.lruph equals the displacement of the car. How long must the brakes be applied for the car to come to a stop in 50 m? Vr'rql U'qþ V:'. ÁX'a trv e sorvì ' u;:I,ß tlf Vtt, V,'¿ t ?.q Àf'20 : _t ôä=2s!+kr¿sl)tls lò^16 ötl ï-- 4s q'-cz-, 1. -t*,?.5nlg:' ôfgraph. quantitative you velocity vs time d. Nbw that know the total time of travel, sketch a t, trT A\b xtÀ I ? ttttlll J - - - ¡ - - -L - - J- - -L - - J--!I tttttll I ttttttl ttttttl I l 2t I I I I I I 4rì t) ¿¡l - - J- Io l-----I I 5 fl e .ps..j;'* _t I I I tl tt tl tl tt tt - -L - - J tt tt tt I I I I I I - - lI I I - - -J- I 5 I I I I J- -!- -+-- -rI I I I I - I --1 I I I I -tI I I - -r-I I I ,J n,lrn I 1 L ',1, j I I I I I I I I I I I I I I I L.(, 5 -i I I I r I t (sI ,1, .J ,,.,,|,,,,,1.,,. lo '1 What acceleration is provided by tÉe\brakes? How do you know? Q: ¿# I @Modeling Workshop Projecl 2002 -?5 4, b ,z.i L{ 3 3 n borsÐ t-{ : Dnn'l t: I I -L I ¡ {r, Unit III ws3 v2.0