bodies in motion will remain in motion and bodies at rest will remain at rest unless acted upon by a net force.
Because that is how inertia is defined!
The Concept of Inertia is defined in Newton's First law of Motion.
the Law of Inertia state
Newton's first law is sometimes called the law of inertia.
Another name for Newton's first law is "the law of inertia."
the first law of motion deals with inertia. it describes about the inertia or the tendency of a body to remain in rest or uniform motion.more over, implicit in the discussion of Newton's first law is the concept of an inertial reference frame, which for the purposes of Newtonian mechanics is defined to be a reference frame in which Newton's first law holds true.There is a class of frames of reference (called inertial frames) relative to which the motion of a particle not subject to forces is a straight line.hence newtons first law is also called law of inertia.
Law of inertia.
It is sometimes referred to as the law of inertia.
Law of Inertia.
The law of inertia is often called Newton's first law of motion.
the law of inertia
This is because the concept of inertia is introduced in the first law of motion.