Question

A 20 kg box rests on a table. Identify the three action-reaction force pairs involved in the box sitting on the table.

Answer 1

A 20 kg box on a table is involved in three action-reaction force pairs: the weight of the box and the normal force, the gravitational forces between the Earth and the box, and possibly the frictional forces if any exist.

Step-by-step explanation:

The situation of a 20 kg box resting on a table involves three important action-reaction force pairs as described by Newton's Third Law of Motion. These force pairs are:

• The weight of the box on the table (action) and the table pushing up against the box (reaction), which we call the normal force.
• The gravitational pull of the Earth on the box (action) and the box's gravitational pull on the Earth (reaction).
• If we consider the table as part of the Earth, then the third pair might involve any additional forces such as friction between the box and the table, with the table exerting a frictional force on the box (action) and the box exerting an equal and opposite frictional force on the table (reaction).

Using Newton's laws, we can calculate these forces quantitatively, ensuring a balanced system where the box remains at rest.