Pulling out a book (friction problem)

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To pull both books along the table, the force F must exceed the static friction force, calculated as F > µ1(m1 + m2)g. For pulling out only the lower book, the force must also surpass the static friction, requiring F > µ1m1g while ensuring it exceeds the dynamic friction force, F > µd(m1 + m2)g. The discussion emphasizes the need to analyze the problem in two parts for clarity. Participants seek precise values for F in both scenarios without extraneous information. The conversation highlights the importance of clear reasoning and accurate calculations in physics problems.
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Two books are lying on top of each other on a table. The upper book has a mass m1 , and
the lower book has a mass m2 . The coefficient of static fric-
tion between the books is µ1 . The coefficient of static friction
between the book and the table is µ2 and the coefficient of
dynamic friction between the book and the table is µd . You
pull on the lower book with a horizontal force F .

(a) How large must F be for you to start pulling both books
along the table.

(b) How large must F be for you to pull out only the lower
book? (a) I reasoned that to get the books going at all we must have that F> \mu_s(m_1+m_2)g and then once it is going we must ensure that \mu_1 m_1g > F > \mu_d(m_1+m_2)g

(b) To get the book going we must again have that F> \mu_s(m_1+m_2)g, but then once it is going F > \mu_d(m_1+m_2)g \wedge \mu_1 m_1g.

Is this the correct reasoning here? We must split the problem up in two parts right?
 
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Noone who can help me with this?
 
You seem to have a lot of extra stuff in your response. Part a asks for the value of F required to move the books. Please provide one answer only for the value of F in part a and correct any typos.

For part b, again provide one answer and correct any typos. Whats that ^ in your equation??
 
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