- #36
SammyS
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In my experience, textbooks generally refer to the NET force acting on a body: the net force being the resultant of ALL of the forces acting on a body.
Newton's 1st Law is sometimes written with reference to net force. Sometimes it's written without reference to net force, only referring to what happens to the body unless some force acts on the body.
Newton's 2nd Law, unless it's written in terms of impulse and momentum, is always written (in my experience) with reference to the net force acting on a body.
Net force has no place in Newton's 3rd Law.
Newton's 1st Law is sometimes written with reference to net force. Sometimes it's written without reference to net force, only referring to what happens to the body unless some force acts on the body.
Newton's 2nd Law, unless it's written in terms of impulse and momentum, is always written (in my experience) with reference to the net force acting on a body.
Net force has no place in Newton's 3rd Law.