Pracicing Problem Solving and Graphing
Tes 1: Jan 30, 7pm, Ming Hsieh G20 The Bes Ways To Pracice for Tes Bes If need more, ry suggesed problems from each new opic:
Suden Response Examples A pas opic ha you sill do no undersand. Many: Which equaion o use? (A: Takes pracice!) Many: Insananeous acceleraion (or v) & graphing Why is acceleraion negaive in one of he pracice problems, bu i is raveling in he posiive direcion? Wha is he difference beween consan acceleraion and non-consan acceleraion? I am confused on he acceleraion a each poin in he following scenario: A vehicle is a res, acceleraes and reaches a consan velociy, hen his he brakes and comes o a sop afer a shor ime. Is acceleraion ever negaive in his scenario? Is i 0 when a consan velociy?
Pracice wih Concepual Problems (example from your pracice es) Le s say your car has a consan rae of acceleraion for each case considered below. Saring from res, you ravel a disance of h in one second. Again, sar from res, how many seconds would i ake you o ravel 4 imes ha disance? For comparison, le s ry o guess firs.
Acceleraion Time Graphs Summarized horizonal graph segmens indicae ha he objec has consan acceleraion a horizonal graph segmen on he xxis indicaes ha he objec has consan velociy (zero acceleraion) graph segmens above he xxis imply increasing velociies (no necessarily speeds!!!) graph segmens below he xxis imply decreasing velociies no changes in direcion may be inferred from hese graphs A he inroducory physics level, we ypically only deal wih consan acceleraion siuaions, so acceleraion graphs generally consis of horizonal segmens only.
An objec is speeding up uniformly in he posiive direcion. Which of he following represens his moion? A. +a B. +a C. +a D. +a Q06
An objec is speeding up uniformly in he negaive direcion. Which of he following represens his moion? A. +a B. +a C. +a D. +a Q07
For hese posiion versus ime graphs, how many are changing speed?
No a graphing quesion, bu he nex par will be This is a moion diagram of an objec moving along he x-direcion wih consan acceleraion. Saring wih 1, he dos 1, 2, 3, show he posiion of he objec a equal ime inervals. 5 4 3 2 1 x = 0 A he ime labeled 3, wha are he signs of he objec s velociy v x and acceleraion a x? A. v x < 0, a x = 0 B. v x < 0, a x > 0 C. v x < 0, a x < 0 D. v x > 0, a x > 0 +x E. v x > 0, a x < 0 Q08
This is a moion diagram of an objec moving along he x-direcion wih consan acceleraion. Saring wih 1, he dos 1, 2, 3, show he posiion of he objec a equal ime inervals. Q09 5 4 3 2 1 x = 0 Which of he following velociy versus ime graphs bes maches he moion shown in he moion diagram? v x v x v x v x +x v x 0 A. 0 B. 0 C. 0 D. 0 E.
Le s Draw Some Graphs! Le s pick an origin and hen draw he posiion, velociy and acceleraion versus ime graph for he following siuaion: Me sanding sill How would hese change if I moved he origin? Me moving o lef a consan speed Me saring from res and speeding up uniformly o he lef A ball afer lef my hand going up and hen falling down
Relaing he Graphs Inegraion (calculus) les you find he area under a curve (which allows you o go backwards), which we won be doing
Velociy and Posiion vs Time Graphs
Clicker Answers Chaper/Secion: Clicker #=Answer Ch.2A: 1=E, 2=E, 3=D Ch.2B: 4=D, 5=B, 6=C, 7=A, 8=C, 9=E