DEPARTMENT OF PHYSICS
PHYS*1000 WEEKLY GUIDE #4
Fall 2009
A. READING/REFERENCE
 Lecture Notes: Mon. Oct. 5 to Fri. Oct. 9
 Textbook: Ch. 4 — Newton’s Laws of Motion
Ch. 5 — Applying Newton’s Laws (but skip the subsection “Fluid Resistance
and Terminal Speed” and the section “The Fundamental Forces of
Nature”)
 Computer tutorials (www.physics.uoguelph.ca/tutorials/tutorials.html)
• Free-body Diagrams (an important one!)
• Vectors • Trigonometry
MasteringPhysics Assignment Deadlines
Assignment #3 (Ch. 3 -- 2-D Kinematics, & Ch. 9 -- Rotational Kinematics):
Monday, Oct. 5, 11:59 p.m.
Assignment #4 (Ch. 4 & 5 – Newton’s Laws of Motion): Thursday, Oct. 15, 11:59 p.m.
Assignment #5 (Ch. 6 & 7 – Work & Energy): Thursday, Oct. 22, 11:59 p.m.
Upcoming Tutorials/Labs:
Oct. 6-Oct. 8: Laboratory experiment #2 (bring Lab Manual) in MacN 301
Oct. 13-15: Tutorial & Quiz #2 in MacN 401 — Quiz #2 will cover the following:
• 2-D kinematics (ref. Ch. 3 and Weekly Guides #2 and 3)
• Rotational kinematics (ref. Ch. 9 and Weekly Guide #3)
• Newton’s laws(1st & 2nd) of motion (ref. Ch. 4 and 5, and Weekly Guides #3 and #4)
The quiz will have questions similar to, but not identical to, the Exercises or Problems on
Ch. 3, 4, 5, and 9 in Sections B and C on Weekly Guides #2, 3, and 4. You may use your
textbook when writing your quiz, but you may not use any written notes.
Oct. 20-22: Tutorial (no quiz) in MacN 401.
B. EXERCISES *
†
an asterisk means that an answer, a hint, or other additional information
is provided in section E of this guide
a dagger means that a complete solution is provided in the “Student Solutions Manual for
University Physics, 12th Edition, by Young & Freedman” that is available at the Library
Reserve Desk, listed under course PHYS*1000 and Prof. E. McFarland.
Ch. 5, #5.29†, 5.37†, 5.34* 5.43 (a)†, 5.52*, 5.54*
[11th edition, #5.23†, 5.31†, 5.28*,5.37 (a)†, 5.46*, 5.48*]
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Multiple-Choice Exercises
1*.
(from midterm exam Fall 2004; 66% of the students answered this question correctly)
A ball is attached to one end of a stiff wire, and a person then holds the other end of the wire and
swings the ball in a vertical circle. When the ball is half-way up along the circle (at this point the
wire is horizontal), which of the following is the correct list of forces acting on the ball? Neglect
air resistance.
(A)
gravity downward, tension horizontally, and the centripetal force
(B)
gravity downward, and tension horizontally
(C)
gravity and tension downward
(D)
gravity and tension downward, and the centripetal force
(E)
gravity downward
2*.
(from midterm exam Fall 2004; 67% of the students answered this question correctly)
A skier of mass 75 kg is standing on a hill that is inclined at an angle of 71° to the vertical. If the
force of gravity on the skier is broken into components, one of which is directed along the hill,
and the other is directed perpendicular to the hill, what is the magnitude of the component that is
perpendicular to the hill?
(A) 2.4 × 102 N
(B) 2.8 × 102 N
(C) 6.9 × 102 N
(D) 7.4 × 102 N
(E) 5.6 × 102 N
C. PROBLEMS
Ch. 5, #5.65†*, 5.66*, 5.67†*, 5.85†, 5.91†*, 5.95†*, 5.104*
[11th edition, #5.60†*, 5.61*, 5.62†*, 5.83†, 5.89†*, 5.94†*, 5.104*]
D. ADDITIONAL EXERCISES AND PROBLEMS (optional extra practice)
Ch. 5, #5.83†, 5.109†, 5.113† [11th edition, #5.81†, 5.109†, 5.113†]
E. ANSWERS, ADDITIONAL INFORMATION
Multiple-Choice Answers:
1. B
2. C
Answers to textbook questions:
#5.34 [11th edition, #5.28] ans. (a) 54 m (b) 16 m/s
#5.52 [11th edition, #5.46] ans. (a) 6.19 s (b) no
#5.54 [11th edition, #5.48] ans. (a) 0.269 (b) 0.0667 m
#5.65 [11th edition, #5.60] ans. (a) m2 = m1 (sinα + μK cosα) (b) m2 = m1 (sinα − μK cosα)
(c) m1 (sinα − μS cosα) ≤ m2 ≤ m1 (sinα + μS cosα)
th
#5.66 [11 edition, #5.61] ans. (a) 12.0 N (b) 15 N
#5.67 [11th edition, #5.62] ans. (a) 1.44 N (b) 1.80 N
#5.91 [11th edition, #5.89] ans. to second part of question: Relative to the cart, the block is at rest.
#5.95 [11th edition, #5.94] ans. 0.34
#5.104 ans. (a) 31.0 N (b) 45.0 rpm (c) 29.9 rpm
(d) still conical pendulum, but smaller angle
2