Question

A 0.5 kg book rests on a table. A downward force of 9N is exerted on top of the book by a hand pushing down on the book.

(a) what is the magnitude of the gravitational force acting upon the book?
(b) what is the magnitude of the upward (normal) force exerted by the table on the book? (is the book accelerated?)

Answer 1

Mass of the book = 0.5 kg

Acceleration due to gravity = 9.8 m/s^2

a) Gravitational force = mass × gravity

Gravitational force = 0.5 × 9.8 = 4.9 N

Hence, the gravitational force = 4.9 N

b) Normal force (N) = Downward force + Gravitational force

Normal force = 4.9 + 9

Normal force = 13.9 N

Hence, the upward normal force applied by the table on the book is 13.9 N

No, the book is not accelerated because the net force on the book is zero.

Answer 2

(a) w=mg so w=.5x9.8=4.90N

(b)13.90N

The book is not accelerated