A student holds a physics book in her hands motionless 1.2 meter above the floor

Question

A student holds a physics book in her hands motionless 1.2 meter above the floor as shown to the left. The forces from her hands on the front and the back of the book are perpendicular to the book's cover and are horizontal. The mass of the book is 33.0 kg. The coefficient of static friction betweent the covers and her hands is ?s=0.49 and the coefficient of kinetic friction is ?k=0.34.
1) What is the net force on the book in the x (horizontal) direction?
?Fx =

N
2) What is the net force on the book in the y (vertical) direction?
?Fy =

N
3) What is minimum normal force that the student can apply from each hand to the cover of the book to keep it from slipping through her hands?
Fmin =

N

Explanation / Answer

There's superfluous information in this question. 35kg x 9.8 = 343N. .45 of 343N = 154.35N will be required to hold the book from slipping. I am assuming she holds the book between both hands (1 each side), not between fingers and thumbs. Halve the above if between fingers and thumbs.

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