Imagine that you are holding a book weighing 4 N at rest on the palm of your hand. Complete the following sentences:
(a) A downward force of magnitude 4 N is exerted on the book by _____ .
(b) An upward force of magnitude is exerted on by your hand.
(c) Is the upward force in part (b) the reaction to the downward force in part
(a)?
(d) The reaction to the force in part (a) is a force of magnitude ____ exerted on by . Its direction is.
(e) The reaction to the force in part (b) is a force of magnitude • exerted on by ____ . Its direction is.
(f) The forces in parts (a) and (b) are equal and opposite because of Newton’s ____ law.

(g) The forces in parts (b) and (e) are equal and opposite because of Newton’s law. Now suppose that you exert an upward force of magnitude 5 N on the book.
(h) Does the book remain in equilibrium?
(i) Is the force exerted on the book by your hand equal and opposite to the force exerted on the book by the earth?
(j) Is the force exerted on the book by the earth equal and opposite to the force exerted on the earth by the book?
(k) Is the force exerted on the book by your hand equal and opposite to the force exerted on your hand by the book? Family, suppose you snatch your hand away while the book is moving upward
(l) How many forces then act on the book?
(m) Is the book in equilibrium?