Physics 170
Mechanics I
(for Engineers)
Prof. Thomas Mattison
Phys 170 Lecture 1
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Goals for Today
Administrivia
Contact info, web pages, etc
Textbook
“Mastering Engineering” (on-line homework)
Tutorial Quizzes
Grading
Rules
Syllabus
Chapter 1
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Where, When, & Who
Lectures: MWF, 2 PM, Hennings 200
Tutorials: Tuesday
1 PM, Hebb 10
2 PM, Math 203
3 PM, Neville Scarfe (Education) 1005
4 PM, Hebb 12
Office Hours: Thursdays 10 AM to 1 PM
or email and ask for an appointment at some other time
Prof. Thomas Mattison
mattison@physics.ubc.ca
Hennings 276 (south corridor, enter at E or W end of building)
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Web Pages
www.physics.ubc.ca/~mattison/Courses/Phys170
Announcements, lecture notes, quiz & exam solutions, etc
Tilda (~) and capitalization is significant
elearning.ubc.ca/connect
Same as above, plus quiz & exam grades
www.MasteringEngineering.com
homework, homework grades
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Textbook
Engineering Mechanics: Statics & Dynamics; R.C. Hibbeler
“2d Custom Edition” (paperback reduced 13th Ed) in bookstore.
Written as separate books “Statics” and “Dynamics,” it’s available either combined or separately. Page numbers reset, chapter
numbers don’t. One table of contents in the front, one set of
appendices in the back, but index and problem solutions in both
middle and end.
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Homework
Weekly homework is on-line via “Mastering Engineering.”
http://www.MasteringEngineering.com
You will need an “access code.” It’s shrink-wrapped with the
textbook at the UBC Bookstore (also an iClicker coupon, which
you won’t need for this course). Or, buy online at above URL.
You need to select the correct textbook (Statics AND Dynamics
13th Ed by Hibbeler, NOT Statics-only or Dynamics-only,
NOT 12th Ed), then enter the course code:
UBCPHYS170FALL14
no spaces, but upper/lower case is irrelevant.
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Homework (2)
Mastering Engineering uses Flash, pop-up windows, cookies,
and Javascript (but not “real” Java).
Works with Firefox, Internet Exploder, Chrome, Safari,
on Mac, Windows, Linux, Chromebook.
iPads and most Android tablets don’t have Flash, so native
browsers won’t work.
But the Puffin browser does work, mostly. There’s a timelimited free version; the full version is a few dollars.
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Packages and Prices
Bookstore:
$160 Cdn + tax for paperback Hibbeler + Mastering Eng
A very few used copies are also at the Bookstore
Online:
$80 US (~$87 Cdn) for Mastering Engineering access only
$145 US (~$158 Cdn) with e-book (that 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.....
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Quiz-Tutorials
Hebb 10 or 12, on Tuesdays, 4 sections, at 1, 2, 3, 4 PM
First half of each “tutorial” will be a quiz:
Do and hand in a written problem.
So bring ruler (for diagrams), calculator, etc.
Closed book, but one page (both sides) of handwritten notes OK
Second half of “tutorial” will be doing the same or similar
problem again, in small groups, to hand in for a group grade.
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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 can’t use your cell-phone as a calculator
(we couldn’t enforce that you weren’t texting for help...)
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Office Hours
Online homework will be due at 5:55 PM on Saturdays,
and new assignments will be posted at 6 PM on Saturdays.
Office Hours: Thursdays 10 AM to 1 PM
or email and ask for an appointment at some other time
mattison@physics.ubc.ca
Hennings 276 (south corridor, enter at E or W end of building,
and go up a half-flight of stairs)
Don’t be scared of office hours. You learn more from face-toface interactions, and I learn more about what students are
having trouble understanding.
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Registration
Last day to drop courses cleanly is Tuesday Sept 16
Last day to drop courses with “W” is Friday Oct 10.
For registration issues, go to Eileen Campbell, Hennings 333A,
or email enph@physics.ubc.ca
You must go to the tutorial section you have been assigned
(we may allow some controlled trades, but not yet...)
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Lecture & Tutorial Courtesy
Turn your cell-phone to vibrate, and call back after class.
No open laptops (YouTube, World of Warcraft is distracting....)
If you really type lecture notes into your laptop,
come to me to get an exception.
Tablets are OK, if they are flat on your desk/lap.
No earphones.
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Grades
10% from Mastering Engineering homework (drop lowest 2)
10% from tutorial quizzes (drop lowest 2)
20% from midterm (probably Friday Oct 10)
60% from final exam
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Academic Integrity
www.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).
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Syllabus
Statics
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 (sliding, static)
Dynamics
Ch. 12: Kinematics (v, a, t-, x-dependent, cylindrical coords)
Ch. 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
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Syllabus (2)
We will basically do a chapter a week.
We only do a subset of the friction chapter.
The midterm will cover through statics.
We will slow down for the dynamics chapters.
We only do a subset of the rotational dynamics chapters,
in less than 3 weeks.
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Calculus
Statics doesn’t use calculus (except a few mini-max problems),
but lots of vectors, which implies trigonometry.
Dynamics uses calculus: differential, integral, some diff. eqns.
Most students take Phys 170 in second term of first year, after
taking one term of differential calculus, and while taking the
second term of integral calculus. So differential is a pre-req,
and integral is a co-req.
They turn off pre-requisite and co-requisite checking for this
course, and many of you don’t satisfy them.
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Calculus Assay
Please pick up the calculus assay, do it, and turn it in on Friday.
It won’t be part of your grade, there’s not even a place to write
your name. It’s just so I have a better feeling for the typical
background level of the students.
You should be able to do the derivatives part easily, and at least
some of the integral part now, and the rest by halfway through
the term.
If you aren’t comfortable with calculus, this is probably not the
course for you, at least not right now....
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Chapter 1: 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.
Weight is a force, NOT a mass.
W = mg g = 9.8066 m/s
2
Some problems in the book and Mastering Engineering use
US units (feet, seconds). Pound is the unit of force, not mass!
A force of 1 pound will cause a mass of 1 slug to accelerate
at 1 foot per second per second.
1 slug has a weight of 32.2 pounds. W = mg g = 32.2 ft/s 2
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Chapter 1: Symbols
Distance
meter (m)
foot (ft)
Time
second (s)
second (s)
Mass
kilogram (kg) slug (
)
Force
Phys 170 Lecture 1
Newton (N)
pound (lb)
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Chapter 1: Prefixes
Phys 170 Lecture 1
G
10 +9
M
10
+6
mega
k
c
m
µ
10 +3
−2
10
10 −3
10 −6
kilo
centi
milli
micro
n
p
10 −9
10 −12
nano
pico
giga
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Chapter 1: Unit Arithmetic
Units can be multiplied, divided, or cancelled.
One Newton times one meter is one Newton-meter or N ⋅ m .
Addition and subtraction require the units to match.
You have to convert units for one or both quantities.
1 inch = 2.540000 centimeters (this is the exact legal definition).
1 kg weighs 2.205 pounds.
1 foot = 12 inches
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1 mile = 5280 feet
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Unit Arithmetic Example
Convert 30 miles per hour to meters per second.
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Unit Arithmetic Example
Convert 30 miles per hour to meters per second.
Since 5280 ft = 1 mile,
5280 feet
=1 .
1 mile
Multiply 30 miles/hr by “1” repeatedly, so the units cancel.
miles 5280 feet 12 inches 0.0254 meters
1 hour
1 minute
30
×
×
×
×
×
hour
1 mile
1 foot
1 inch
60 minutes 60 seconds
30 ⋅ 5280 ⋅12 ⋅ 0.0254
meters
=
= 13.41
60 ⋅ 60
second
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For Next Time
Pick up the Calculus Assay, do it, and bring it to class Friday.
Register for Mastering Engineering, and start the practice
assignment (due 5:55 PM on Saturday).
Get the textbook, read Chapter 1, and Chapter 2 sections 1-4
(two-dimensional vectors, and simple vector operations)
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Web Pages, Etc
www.physics.ubc.ca/~mattison/Courses/Phys170
Lecture notes, quiz & exam solutions, etc
Tilda (~) and capitalization is significant
elearning.ubc.ca/connect
Same as above, plus quiz & exam grades
UBCPHYS170FALL14
Hibbeler, Statics & Dynamics, 13th Ed
www.MasteringEngineering.com
Homework
mattison@physics.ubc.ca
Me
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