Inertia of a mass in vacuum of space

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SUMMARY

The discussion centers on the concept of inertia in a vacuum, specifically regarding the immediate response of an object to an applied force. According to Newton's 2nd Law, an object in free space will begin to accelerate immediately upon the application of force, regardless of its mass. The conversation highlights that while inertia may suggest a delay, the absence of friction means that acceleration occurs without any time lag, although initial accelerations may be too small to observe. The nuances of contact forces and their effects on acceleration are also explored, emphasizing that the perception of inertia may be influenced by the nature of the force applied.

PREREQUISITES
  • Understanding of Newton's Laws of Motion
  • Familiarity with concepts of inertia and acceleration
  • Basic knowledge of forces in a vacuum
  • Awareness of the effects of friction on motion
NEXT STEPS
  • Study Newton's 2nd Law of Motion in detail
  • Explore the concept of inertia and its implications in physics
  • Research the behavior of objects in a vacuum using simulations
  • Investigate the effects of different forces on acceleration in various environments
USEFUL FOR

Physics students, educators, and anyone interested in the principles of motion and forces in a vacuum will benefit from this discussion.

Gear300
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A thought just sort of popped out presenting a question I'm not sure I've ever answered:

An object is in free space with no friction present throughout the surroundings. A person is placed near the object and decides to push the object away from him/her. There is no friction present. What I'm wondering is if the object immediately moves when the force is applied. If the object has a mass and hence, inertia, shouldn't there be some sort of time lag before it started to move?
 
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If there is no friction at all, then as soon as a force is applied to any object it begins to accelerate (according to Newton's 2nd Law), which means it's motion changes immediately.

In all cases of contact forces between two objects, the net force on one object is not constant; it begins as infinitesimally small and proceeds quickly to a maximum, then trails off to zero again. So all accelerations begin as infinitesimally small. Depending on the nature of the contact and the masses of the objects, this initial acceleration may or may not be observable. If it is, then it might appear that the object does not accelerate at first, when in fact the acceleration is there, but too small to observe.
 


I see, I see...so is inertia is something characteristic of how long it takes applied energy to distribute across a mass?
 
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