What is the significance of Newton’s first law?

Isaac Newton’s first law of motion, also known as the law of inertia, states that a stationary object will remain at rest and a moving object will move in motion at the same speed and direction unless an unbalanced force is applied. In other words, if no force acts on the object, it will maintain a constant speed (for a stationary object, this speed is zero). With the first law of motion, Newton established the existence of a frame of reference for which his other laws of motion, called the inertial frame of reference, are applicable. An inertial frame of reference is one in which the observer moves at a constant speed (including stationarity).

To understand the purpose and application of Newton’s I law, one should imagine a body at rest, that is, other objects do not act on it. This example is the simplest mechanical type system. If we assume the existence of another object that moves under the influence of external forces, relative to the desired body.

The center of the frame of reference for a moving object is a body whose velocity is 0 (v = 0). Newton’s first law is formulated as follows: in inertial reference frames (IFR), bodies move uniformly and rectilinearly, and can also be at rest when they do not interact with other bodies or external forces do not act on them (their action can be compensated).

The significance of Newton’s first law is that it establishes the existence of inertial frames of reference (such frames of reference relative to which bodies move at a constant speed while compensating for external influences). It is for such frames of reference that all other Newton’s laws are valid.