Question

1. do two bodies have to be in physical contact to exert a force upon one another? give an example of this.

Explanation:

To determine if two bodies need physical contact to exert a force, we analyze force types. Contact forces (like friction, normal force) require contact, but non - contact forces (field - based) do not. Gravitational force is a non - contact force: the Earth and the Moon exert gravitational force on each other without touching. Another example is magnetic force (e.g., a magnet attracting a paperclip from a distance) or electrostatic force (e.g., a charged balloon attracting hair without contact).

Answer:

No, two bodies do not have to be in physical contact to exert a force upon one another. For example, the gravitational force between the Earth and the Moon (or between the Earth and an apple in free - fall) is a non - contact force. The Earth exerts a gravitational pull on the Moon, and vice versa, without them being in physical contact. Another example is the magnetic force: a magnet can attract a paperclip from a short distance away, exerting a force on the paperclip without touching it.