Here's the breakdown:
Forces always come in pairs. This is the essence of Newton's Third Law. When one object exerts a force on another object, the second object exerts an equal and opposite force back on the first object.
Example:
* You push a wall: You exert a force on the wall. The wall, in turn, exerts an equal and opposite force back on you. This is why you feel the wall "pushing back".
* A book on a table: The book exerts a force on the table due to gravity (its weight). The table exerts an equal and opposite force upwards on the book, preventing it from falling through the table.
However, the effects of the forces can be different.
* You pushing a wall: Even though the forces are equal and opposite, the wall doesn't move because it's much heavier and more firmly anchored than you are. You, on the other hand, feel the force and likely move backwards.
* A book on a table: The forces are equal and opposite, resulting in a balanced situation where the book remains stationary.
In summary:
* Forces are always equal and opposite.
* The effects of these forces depend on the masses and other factors of the objects involved.
