Question

You hold your physics textbook in your hand. (assume that no other objects are in contact with the book.) (a) identify the forces acting on the book. (select all that apply.) book on hand hand on book floor on book earth on book

Answer 1

If the book is still, there are only two forces acting on the book:

1) the weight of the book, which points downwards, equal to the product between the mass of the book and the gravitational acceleration g:
$W=mg$

2) the reaction force of the hand on the book, acting upwards, whose intensity is equal to the weight of the book.