#### Spring 2015 Homework Assignment Page 2 for PH111L (__Fundamentals of Physics I__)

Text: Serway & Jewett *Physics for Scientists and Engineers (8th edition)*

OQ are 'objective questions'. Be prepared to discuss them in class but no need to put answers on paper.

CQ are 'conceptual questions'. Put your responses on paper in coherent elegant prose, using a few full sentences.

P are 'problems'. The answers to the odd-numbered problems are in the back of the book. Put your solutions on paper.

**Assignment 7** (Assgd Tues 17 Mar; Due Thurs 26 Mar)
CH 7 OQ #4, 6, 7, 10 [this one will stretch your brain, even though it is simple]
CH 7 P #1, 6, 12a, 14, 17, 24, 34, 41, 49
CH 8 P #5 [assume mechanical energy conservation], 12, 22, 25, 29, 34
Here are the solutions to homework 7

**Assignment 8** (Assgd Thurs 26 Mar; Due Thurs 9 Apr)
CH 9 OQ # 5, 12, 18
CH 9 P # 1, 3 [hint: what is the 'rate of momentum extraction' by friction on the sled?], 6, [hint: the system CM cannot move], 11,
15, 19, 21, 37, 38, 40 [you must identify the proper *dm* in terms of *λ* and *dx*], read 43, 44
Here are the solutions to homework 8

**Assignment 9** (Assgd Thurs 9 Apr; Due Thurs 16 Apr)
CH 10 OQ # 1 [you might hold off on this one until you've tried some problems], 4, 6,
CH 10 P # 3, 6 [express answer in rad/sec^{2}], 11 [this one synthesizes a couple of ideas from earlier chapters.. basically, find the time the thing needs to fall, and then estimate
how much rotation the building makes in that time, and so you know the linear distance the surface of the earth moves in that time], 19, 22, 26, 29, 33, 35 [note that we could assume the wheel has a fourth force on it at the axle, to insure that
*F*^{net} = 0, but that force won't affect the torque about the axle because its moment arm is zero], 42, 44, 50 [use energy methods]
Here are the solutions to homework 9

**Uncollected Assignment/Assignment 10** (Just some problems to guide you in your study)
CH 11 OQ # 1, 4, 8 [recall that *isolated* means no matter, energy, or forces can enter or leave the system]
CH 11 P # 5 [definitional], 9, play with 19 at least qualitatively, 25, 29 [a rehash of an exam problem], 34 [you can try this out in the lab if you want to -- there's nothing
like actually doing the experiment!]
CH 12 OQ # 2
CH 12 P # 8, 11, 16 [pretty cool!]
Here are the solutions to homework 10