Can one determine that an instrument is an accelerometer locally?

In summary, the conversation discusses determining inertial movement and identifying an accelerometer and vacuum. It is possible to determine inertial movement locally with an accelerometer and to identify an accelerometer and a vacuum by connecting it to ground or using a pump's owner manual. These operations are considered local in terms of GR, meaning they are done over a small enough region of spacetime to neglect curvature.
  • #1
atyy
Science Advisor
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Let's stick to SR here.

Given an accelerometer, one can determine locally if one is moving inertially or not?

Can one determine locally if a particular instrument is an accelerometer? If one has no accelerometer, then inertial movement has to be determined by absence of forces on the body. This can be done by knowing the full distribution of matter in the universe, and ascertaining that that distribution of matter does not exert any force on the particle, which seems to be a global determination?
 
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  • #2
atyy said:
Let's stick to SR here.

Given an accelerometer, one can determine locally if one is moving inertially or not?
Yes.

atyy said:
Can one determine locally if a particular instrument is an accelerometer?
Yes.

atyy said:
If one has no accelerometer, then inertial movement has to be determined by absence of forces on the body. This can be done by knowing the full distribution of matter in the universe, and ascertaining that that distribution of matter does not exert any force on the particle, which seems to be a global determination?
Why would you need to do that? Just make sure the device is uncharged and drop it in vacuum.
 
  • #3
DaleSpam said:
Why would you need to do that? Just make sure the device is uncharged and drop it in vacuum.

How would one make sure the device is uncharged?

And how would one identify a region of space as vacuum? (I guess if it's uncharged, we don't have to drop it in vacuum, since it won't interact with matter anyway, so we just have to determine it's uncharged.)
 
Last edited:
  • #4
atyy said:
How would one make sure the device is uncharged?
Connect it to ground for a little while.

atyy said:
And how would one identify a region of space as vacuum?
Look at the owner's manual for your pump. The region on the "inlet" side will be the one with vacuum.

Look atyy, everything I say you can respond with another series of "how would one" questions. It will get tiresome fast; I get enough of that from my kids (usually "why" questions). Please figure out what your real question is before continuing.
 
  • #5
DaleSpam said:
Connect it to ground for a little while.

Look at the owner's manual for your pump. The region on the "inlet" side will be the one with vacuum.

Are these local operations?
 
  • #6
Yes. This is "local" in the sense of GR. Meaning that it is over a region of spacetime small enough to neglect curvature.
 

1. How can I tell if an instrument is an accelerometer?

The best way to determine if an instrument is an accelerometer is to look at its specifications or documentation. Accelerometers usually have a range of frequencies and acceleration values that they can measure, which can help identify them. Additionally, accelerometers typically have a small mass that moves in response to acceleration, so you may be able to identify one by physically inspecting it.

2. Can I use a multimeter to identify an accelerometer?

No, a multimeter cannot be used to identify an accelerometer. Multimeters are typically used to measure voltage, current, and resistance, and are not capable of measuring acceleration. Additionally, accelerometers require a power source and a circuit to function properly, which a multimeter does not provide.

3. Are there any visual cues that can help me identify an accelerometer?

While there are no universal visual cues that can definitively identify an accelerometer, there are some common characteristics that may indicate an instrument is an accelerometer. These include a small, cylindrical shape, with a connector for attaching to a circuit, and a mass element that can be seen inside the instrument.

4. Can I determine if an instrument is an accelerometer by testing its response to different types of motion?

Yes, you can determine if an instrument is an accelerometer by testing its response to different types of motion. Accelerometers are designed to measure acceleration, so they will respond differently to different types of motion, such as linear or rotational. By testing the instrument's response to these motions, you can determine if it is an accelerometer.

5. Are there different types of accelerometers that may require different methods of identification?

Yes, there are different types of accelerometers that may require different methods of identification. Some common types of accelerometers include piezoelectric, piezoresistive, and capacitive accelerometers, which all use different principles to measure acceleration. Therefore, the methods for identifying these accelerometers may vary, and it is important to consult the instrument's documentation for specific identification techniques.

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