Question

does anyone know what mutual force is?

couldn't find it on google

Answer 1

A mutual force is the interaction force between two objects. Such mutual force can be described by introduction of the concept of \(field\) of forces, namely a geometric or euclidean region wherein such two objects are positioned. With that hypothesis, we can say that a pair of mutual forces (one force, of the pair, for each object) is acting on the two objects, and such pair of forces obeys to the \(3-rd\) Newton's law, even if the question is more subtle, since the interaction can propagate with a determined speed, namely the light speed.