eiinertiaalisesta

The term "eiinertiaalisesta" is a Finnish word that translates to "non-inertial" in English. It refers to a frame of reference that is accelerating. In an inertial frame of reference, objects at rest remain at rest, and objects in motion continue in motion with constant velocity unless acted upon by a net force. This is a direct consequence of Newton's first law of motion, also known as the law of inertia.

In contrast, a non-inertial frame of reference is one that is not accelerating. When observing motion from a non-inertial frame, fictitious forces, such as the centrifugal force and Coriolis force, appear to act on objects. These forces are not real forces in the sense that they are not caused by the interaction between objects. Instead, they are mathematical constructs that arise because the observer is in an accelerating frame. For example, if you are in a car that is accelerating forward, you might feel pushed back into your seat. This sensation is due to the non-inertial nature of your reference frame.

Understanding the distinction between inertial and non-inertial frames is crucial in physics, particularly in mechanics and celestial mechanics. Many physical phenomena, like the apparent deflection of winds and ocean currents due to the Earth's rotation, are best explained by considering the Earth as a non-inertial frame of reference. Calculations in non-inertial frames require the inclusion of these fictitious forces to accurately describe the motion of objects.