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Phys 170 Lecture 1 1
Physics 170Mechanics I (for Engineers)
Prof. Thomas Mattison
Please pick up a handout
Phys 170 Lecture 1 2
About Me
Professor Thomas Mattison experimental particle physics, accelerator physics
Hennings 276 (south corridor, enter at E or W end of building)
Office Hours: Fridays, 12:30 - 2:30 PMor email to ask for an appointment at other times
Phys 170 Lecture 1 3
About Physics 170
Newtonian MechanicsStatics (force balance, moment (torque) balance)Dynamics (F = ma, energy, momentum, angular momentum)
Compared to high school, the problems haveMore steps (but still simple)Often multiple equations in multiple unknowns (but linear)Sometimes equations require numerical solutionCalculus (derivatives up to chain-rule, easy integrals)
The textbook has a range of problems from straightforward(well do mostly those) to quite difficult.
Phys 170 Lecture 1 4
SyllabusStatics
Ch. 2: Force Vectors (vector algebra, components)Ch. 3: Point Equilibrium (free-body-diagram, 3 eqns & vars)Ch. 4: Moments (torque, cross-product, force-couples)Ch. 5: Rigid Body Equilib (force+moment-balance, 6 eqns)Ch. 8: Friction (we only do a few sections)
DynamicsCh. 12: Kinematics (v, a, t-, x-dependent, cylindrical coords)
Midterm ExamCh. 13: Kinetics (F = ma problems in various coords)Ch. 14: Work & Energy (trick for some x-dep force probs)Ch. 15: Momentum (conservation, collisions)Ch. 16-18: Rotational motion, fixed axis or limited to plane
Phys 170 Lecture 1 5
PHYSICS 170 MECHANICS I: SECTIONS 201 and 202 (2017W2) Section 201: 11:00 am to 11:50 am Monday, Wednesday, Friday CHEM B250 Section 202: 2:00 pm to 3:20 pm Tuesday, Thursday WOOD 2
Lecturer: Dr. M. McMillan Professor Emeritus of Physics Office: HENN 303 Email: [email protected]
Text: R.C. Hibbeler, Engineering Mechanics: Statics and Dynamics, Prentice-Hall Publishing Company, Third Custom Edition (of the 14th edition).
LECTURE SCHEDULE
Week Lectures Text Sections Text Problems on Connect Lecture Problems in bold type
1 Jan 3 to 5 1.1-1.6 2.1-2.4 2-44 13e, 2-51 13e, 2-55 14e, 2-57 14e 2 Jan 8 to 12 2.5-2.9 2-78 13e, 2-79 12e, 2-94 13e, 2-100 12e
2-109 13e, 2-120 14e, 2-121 14e 3 Jan 15 to 19 3.1-3.4 4.1-4.3 3-43 13e, 3-52 14e, 3-53 14e, 3-53 12e,
3-58 12e, 3-59 12e, 3-75 12e 4 Jan 22 to 26 4.4-4.8 4-48 14e, 4-53 13e, 4-62 13e, 4-63 13e
4-116 12e, 4-136 13e, 4-137 13e, 4-140 12e 5 Jan 29 to Feb 2 5.1-5.7 5-72 12e, 5-76 12e, 5-78 14e
5-80 12e, 5-82 12e, 5-82 13e 6 Feb 5 to 9 8.1-8.3 8-23 14e, 8-27 12e, 8-55 14e, 8-56 13e,
8-64 13e, 8-67 12e, 8-144 13e, 8-150 12e 7 Feb 13 to 16 12.1-12.7 12-92 12e, 12-97 14e, 12-120 14e, 12-125 12e
12-130 13e, 12-132 13e, 12-142 14e Midterm Break
8 Feb 26 to Mar 2 12.8-12.10 12-176 12e, 12-207 13e, 12-208 13e 12-208 12e, 12-212 13e, 12-225 13e, 12-228 12e
9 March Exam 8:00 pm Tue Mar 6
Mar 5 to 9
13.1-13.5
Chapters 1, 2, 3, 4, 5, 8, 12
13-22 13e, 13-27 12e, 13-32 12e, 13-41 12e 13-46 13e, 13-48 13e, 13-53 12e, 13-54 12e,
10 Mar 12 to 16 13.6 13-104 13e, 13-107 13e, 13-110h 13e, 13-110v 13e, 13-113v 14e 11 Mar 19 to 23 14.1-14.6 14-5 12e, 14-16 13e, 14-33 12e, 14-34 12e
14-41 14e, 14-87 12e, 14-100 12e 12 Mar 26 to Mar 29 15.1-15.4 15-47 12e, 15-52 14e, 15-69 12e, 15-77 14e
15-79 12e, 15-86 12e, 15-87 12e 13 Apr 3 to 6 15.5-15.7 15-101 12e,15-107 13e, 15-108 14e, 15-109 13e, 15-112 13e
MARKS
Final Exam 60 March Exam 30
Mastering Engineering Assignments Tutorial Assignments
5 5
Total 100 You must obtain a total of at least 45 marks out of 90 on the two exams (Final Exam, March Exam) for your marks for Mastering Engineering Assignments and Tutorial Assignments to count towards your Final Grade.
Phys 170 Lecture 1 6
The Cycle
Fundamental problems (solutions in back of book) & M.E. tutorial material appear on M.E. Friday night(covers next weeks material, for zero points).
On the weekend, print out problems we will do in lecture,and skim the chapter (or part of chapter).
Lectures on Monday, Wednesday, Friday + your tutorialMostly well do the problems.
Mastering Engineering homework for points due 10 PM Friday of the next week.
Phys 170 Lecture 1 7
Grades
30% from midterm (8 PM Tuesday March 6)
60% from final exam
You must get at least 45/90 from the midterm+final to add:
5% from tutorial problems
5% from Mastering Engineering homework
Phys 170 Lecture 1 8
Academic Integritywww.vpacademic.ubc.ca/integrity/policies.htm
Cheating includes, but is not limited to: falsifying any material subject to academic evaluation; having in an examination any materials other than those permitted by the examiner; and using unauthorized means to complete an examination (e.g. receiving unauthorized assistance from a fellow student).
Phys 170 Lecture 1 9
OK and Not OK
Its not OK to copy, or help each other, or use wireless devices, books, extra notes on the final or midterm.
Its OK to help each each in tutorials.
Its OK to help each other on homework.
Its not OK to post full solutions (and Ill pull them down).
Phys 170 Lecture 1 10
Tutorials
Tutorials start next week. No tutorials this week.
You must go to the tutorial section you have been assigned.
You will do and hand in an exam-type problem in small groups.
Bring a ruler (for diagrams), calculator, laptop, etc.
Graph paper is useful for diagramsGreen engineering pad is encouraged but not required
Phys 170 Lecture 1 11
Registration
Last day to drop courses cleanly is Wednesday Jan 17.
Last day to drop courses with W is Friday Feb 9.
For registration issues, go to Eileen Campbell, Hennings 333A, or email [email protected]
You must go to the tutorial section you have been assigned
Phys 170 Lecture 1 12
Textbook & Mastering Engineering
Engineering Mechanics: Statics & Dynamics; R.C. Hibbeler
3d Custom Edition (paperback reduced 14th Ed) in bookstore.
Written as separate books Statics and Dynamics, its avail-able either combined or separately. Page numbers reset, chapter numbers dont. One table of contents in the front, one set of appendices in the back, but index and problem solutions in both middle and end.
The problems from the book, plus tutorial material, is athttp://www.MasteringEngineering.com
http://www.MasteringEngineering.comhttp://www.MasteringEngineering.com
Phys 170 Lecture 1 13
Packages and Prices
Bookstore:$189 Cdn + tax for paperback Hibbeler + Mastering Eng$96 Cdn + tax for Mastering Engineering code w/o book
Online:$80 US ($100 Cdn, tax?) for Mastering E. access only$144 US ($180 Cdn, tax?) with e-book (expires with course)
Older-edition Hibbelers (used) are OK, considerably cheaper,and not hard to find. 12th, 11th, even 10th edition is OK.
There are torrents out there too, of course.....
Phys 170 Lecture 1 14
Mastering Engineering
Homework, and extra tutorial stuff (no points), is on-line athttp://www.MasteringEngineering.com
You will need an access code. Its shrink-wrapped with the textbook at the UBC Bookstore (also with an iClicker coupon).Or you can buy it without the textbook. Or, you can buy it online at above URL, with or without e-text.
You will need the course ID to register, which is MWF300PM (no spaces, but upper/lower case is irrelevant)The course ID links you to the correct textbook automatically.
http://www.MasteringEngineering.comhttp://www.MasteringEngineering.com
Phys 170 Lecture 1 15
Mastering Engineering the Hard Way
You need to select the correct textbook:Statics AND Dynamics 14th Ed by Hibbeler, NOT Statics-only or Dynamics-only, NOT 13th Ed or earlier
Phys 170 Lecture 1 16
System Requirements for M.E.
Windows 7 or later, MacOS 10.9 or later (10.6.8 ~ works)(unofficially on Linux, Chromebook)
Chrome, Firefox, Safari, I.E. 11, Edge
Works on IOS 8+ with Chrome and native browser Safari
Works on Android 4.4+ with Chrome (but not native browser)(some features dont work at all, and vector-drawing is poor)
Uses pop-up windows, cookies, and Javascript.Flash and Java still lurk in corners but almost extinct.
Phys 170 Lecture 1 17
iClickers
I will often have clicker questions,so you should bring an iClicker to lecture.
But I just do clicker questions to make you think,so I dont give any points for right or wrong answers.
I dont even give participation points to check attendance.
Phys 170 Lecture 1 18
Calculators
Graphing or programmable calculators OK for quiz & exams.(but we reserve the right to tell you to clear all memory!)
But, no devices with wireless capability (wi-fi or cell).So no laptops, tablets, etc.
Also, you cant use your cell-phone as a calculator(we couldnt enforce that you werent texting for help...)
Phys 170 Lecture 1 19
Calculators (2)
A calculator that solve one non-linear equation, and can do 3 equations in 3 unknowns, is useful, and almost necessary.
Some cheap calculators can do this.
Your old TI-83 or -84 is fine.
If you are going to buy anexpensive calculator, Id pay the few extra bucks to get a TI-Nspire CX instead of a TI-84,and get the CAS (computer algebra system) version
Phys 170 Lecture 1 20
Web Pageshttp://connect.ubc.ca
Should have a link to PHYS 170 (plus your other courses)Course content for all 3 lecture sessions, and grades
http://www.physics.ubc.ca/~mattison/Courses/Phys170
Tilda (~) and capitalization is significantCopy of my part of Connect, intended to be self-contained
http://www.MasteringEngineering.com
Enter class ID MWF300PM Homework, homework gradesAlso Fundamental Problems & M.E. tutorials (zero points)
http://www.MasteringEngineering.comhttp://www.MasteringEngineering.comhttp://www.physics.ubc.ca/~mattison/Courses/Phys170http://www.physics.ubc.ca/~mattison/Courses/Phys170http://www.MasteringEngineering.comhttp://www.MasteringEngineering.com
Phys 170 Lecture 1 21
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Phys 170 Lecture 1 27
Phys 170 Lecture 1 28
Phys 170 Lecture 1 29
a)
b)
c)
PEY$ICS 1?0 MECHANICS I Febnlsry Exam: 8:00 pm to 9:S pm, Trsdey, Febnrary l4,2ql7
gvE'sTloN 2
The diagn*r bclow shos6 a rigid box mtd on by a f,orce Fo at point O,W 1for"" Fu at pointl, and by
acorrplemsm{* d whsr! Fo=gi- zj+SE kN,4 =(17 -l j++f}fr-I,
ft = q-rc{ * ttj + lE|kN. m where l, j,i are the usual Cartesian unit vectors,
Draw a largq clear diagfarn for the hx showing the furcm and the couple moment.
fJetsmine the nsmerical value ofthe momsnt of 4, afout O as a Cartesian vector.
The furces and fte couple rnoment shown on the diagrarn can be replaeed by mr equivalent resutffi
force F* asting d point Bamd a rcsultsrt couple moment (frf olo -
De$smine ths num!rical values of. { "rrCt1&*)" as Cartesian yectsrs.
Are F" mrd {eib awrench? Explainwhyorwhynot.
' \ , .
"!4
d)
3"4
r*r
F!
A5F-r-
Phys 170 Lecture 1 30
FI.{Y$CS }?S MECHA!{IC$ I Febnnr}i Exm: 8:SS pm to 9;S pm, Twdey, Fewf t4,Z*17
OUESTIG.i I
In tb diaeram bdown psticle O is held in equilihium by hrre F ann forces F; ann F" "f*g ** ropes Ol
sd g4 rry!ire*y. The qnin* otr F, * 5 kN. Ths rrqnill* of $ is o R.I.
Tbe mseofFactielo Ory he mele!*d-
aI &arahe, dcufu.bodf d"Srm furFticle CI.
b) Defsrmire tbe coosdisdc dirdim mgls of F^.
c) &emturbpflee{imd f', *qOf,
d) Et*emine eql$iffi af quilibnimforgticte O.
e] trenersisemwiet y&F fu rb Ccsesislcoqcpsrcrrts of F"
Phys 170 Lecture 1 31
Phys 170 Lecture 1 32
Phys 170 Lecture 1 33
Outside of ConnectConnect version
Phys 170 Lecture 1 34
Chapter 1
Basically just about units, almost no content
Phys 170 Lecture 1 35
SI Units
Mostly we use SI units (meters, kilograms, seconds).
The SI unit of force is the Newton: the force that causes a 1 kg mass to accelerate at 1 meter per second per second.
Phys 170 Lecture 1 36
Unit Arithmetic
Units can be multiplied, divided, or cancelled.
One Newton times one meter is one Newton-meter or .
One meter per second-squared times one second
is one meter per second:
Things must have the same units if added or subtracted!
N m
1ms2
1s( ) = 1
ms
Phys 170 Lecture 1 37
Unit Conversions
Take an equation like
Turn it into an expression for the number 1
or
Multiply initial value with units by the appropriate 1 and cancel the units:
1 m = 1000 mm
3.14159 m 1000 mm1 m
= 3141.59 mm
1 m1 m
=1000 mm
1 m1 = 1000 mm
1 m
1 m1000 mm
=1000 mm1000 mm
1 m1000 mm
= 1
Phys 170 Lecture 1 38
Mass vs Weight
Weight is a force, NOT a mass.
Standard g = 9.80665 m/s2.
Actual g varies from9.780 at the equator to9.832 at the poles!
In Vancouver at 49 N,g = 9.81 m/s2.
W = mgg = 9.8 m/s2
Phys 170 Lecture 1 39
US Units
Some problems in the book and Mastering Engineering use US units (feet, pounds, seconds).
One inch is legally defined as 2.54 centimeters exactly.One foot is 12 inches. One mile is 5280 feet.
One pound is defined as the force from exactly 0.45359237 kgin standard gravity of 9.80665 m/s2, or 4.4482216 Newtons.
Phys 170 Lecture 1 40
Mass in US Units
Pound is the unit of force, not mass!
The US unit of mass is the slug.
A force of 1 pound will cause a mass of 1 slug to accelerateat 1 foot per second per second.
W = mg is still true, with g = 32.2 ft/s2
Phys 170 Lecture 1 41
Vancouver Slug Weighs 32.185 Pounds
Phys 170 Lecture 1 42
Unit Symbols
Distance meter (m) foot (ft)Time second (s) second (s)Mass kilogram (kg) slug ( )Force Newton (N) pound (lb)
Phys 170 Lecture 1 43
Prefixes
G 10+9 gigaM 10+6 megak 10+3 kiloc 102 centim 103 milli 106 micron 109 nanop 1012 pico
Phys 170 Lecture 1 44
For Next Time
Find the course web page on Connect, and my versionhttp://www.physics.ubc.ca/~mattison/Courses/Phys170
Get the textbook, read Chapter 1, and start reading Chapter 2.
Get an access-code for Mastering Engineering.Enter class ID MWF300PM
For Friday, bring todays handout, your iClicker, (graph) paper, ruler & calculator if you want.
http://www.physics.ubc.ca/~mattison/Courses/Phys170http://www.physics.ubc.ca/~mattison/Courses/Phys170