Question

a rocket moves forward because the gases exert an opposite and equal force(reaction).but why a book lying on a table doesn't moves as the table also exert an opposite and equal force(reaction)?????please explain it

Answer 1

the weight of the book dominates the reaction given by table to the book.thats why the resultant force acts downward and doesnot move. as we know the base area of book is large thats whi its momentum is spread whole over the table and it doesnot get sufficient kinetic energy to move or bounce again.

In case of rocket the upward thrust applied by the burning fuel is more than the weight of rocket so resultant force acts upward and rocket moves up.