For those who have this textbook.

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The discussion revolves around a question from Physics for Scientists and Engineers Volume 1 regarding the omission of friction forces in several problems. Users express confusion about why friction is not considered in the solutions provided in the answer key. It is noted that friction is often ignored in educational contexts to simplify concepts. Clarification is sought on the labeling of coefficients of friction, which are correctly identified as μ1 and μ2 in the textbook. The overall sentiment reflects frustration with the perceived inaccuracies in the textbook's presentation of friction concepts.
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Homework Statement



In Physics for Scientists and Engineers Volume 1 Eighth Edition (Serway, Jewett)

Number 55. in Chapter 5, I checked the answer key and would like to know why they don't consider the forces of friction in a), b), c), d), and e)? This confuses me. Thank you.

Homework Equations



F = ma

The Attempt at a Solution



The solutions for f and g I got right.
 
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I don't have the book, what is the actual question?

Many times friction is ignored in order to explain concepts with simplicity.
 
QuarkCharmer said:
I don't have the book, what is the actual question?

Many times friction is ignored in order to explain concepts with simplicity.

I found it online:

http://www.cramster.com/answers-sep-10/physics/blocks-masses-m1-m2-nbsptwo-blocks-masses-m1-m2-table_950775.aspx

The answer key gives:

b) F, c) F - P, d) P, e) m1: F - P = m1a; m2: P = m2a

I want to add that obviously in the book the coefficients are labeled "mu"1 and 2
 
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DannyPhysika said:
Number 55. in Chapter 5, I checked the answer key and would like to know why they don't consider the forces of friction in a), b), c), d), and e)? This confuses me.
Seems just wrong to me.

Does the book really say: "The coefficient of kinetic friction between the block of mass m1 and the table is m1, and that between the block of mass m2 and the table is m2." That makes no sense! (Maybe μ1 and μ2?)
 
DannyPhysika said:
I want to add that obviously in the book the coefficients are labeled "mu"1 and 2
That's better.
 
Doc Al said:
Seems just wrong to me.

Does the book really say: "The coefficient of kinetic friction between the block of mass m1 and the table is m1, and that between the block of mass m2 and the table is m2." That makes no sense! (Maybe μ1 and μ2?)

Yeah it's actually labeled μ in the book
 
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