# Inertia? what is its origin

1. Jan 7, 2014

### zepp0814

Hi, so i have a fairly good understanding of most of the concepts relating to inertia. but my question is what is the force felt by the observer while accelerating. for example the force gravity can be described as space bending into shapes around the body of mass, the other can be described as the exchange of quantum particles and other such as centripetal force as simply felt because we want to be traveling in a straight. so once again what is the causes the force of inertia.

2. Jan 7, 2014

### ZapperZ

Staff Emeritus
And what exactly have you understood here?

Zz.

3. Jan 7, 2014

### HallsofIvy

There is no "force of inertia". If you are sitting in a car that accelerates from 0 to 60 mph, I presume that you will want to accelerate with it! And that requires that a force be applied to you. If you are really concerned about "quantum particles" then it is a matter of electro-magnetic forces. The electrons in the seat push against the electrons in your body.

4. Jan 8, 2014

### CWatters

Acceleration is defined as a change in velocity. Velocity has components speed and direction. If you change either the speed or the direction then you change your velocity and that means you are accelerating. So the force you feel when rotating is also a "force felt by the observer while accelerating".

5. Jan 8, 2014

### CWatters

Perhaps what you are really asking is "What gives objects mass"?

The short answer is we don't know. One theory is that it's caused by the Higgs particle interacting with the Higgs field.

or perhaps you wan to know the source of inertia...

http://en.wikipedia.org/wiki/Inertia#Source_of_inertia