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Author Topic: Does an object accelerating in an none inertial reference frame continue to ..?  (Read 1916 times)

Offline Thebox

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Does an object accelerating in an none inertial reference frame continue to accelerate if there is no external acting force?



 

Offline alancalverd

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Offline Thebox

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No

Thank you for the direct no fuss answer .

Does an object continue to accelerate in an inertial reference frame even though it is relatively not moving?



« Last Edit: 07/03/2016 13:03:50 by Thebox »
 

Offline alancalverd

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relative to what?
 

Offline Thebox

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relative to what?

Relative to the ground, even though I am now relatively stationary to the ground (sitting), am I still accelerating?


 

Offline evan_au

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Quote from: TheBox
even though I am now relatively stationary to the ground (sitting), am I still accelerating?
Yes. The seat is applying a force to your backside, which is accelerating you upwards (F=ma, as per Newton).

This upwards acceleration exactly counteracts your natural tendency (in an inertial frame) to plunge towards the center of the Earth in an elliptical orbit.
 

Offline Thebox

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Quote from: TheBox
even though I am now relatively stationary to the ground (sitting), am I still accelerating?
Yes. The seat is applying a force to your backside, which is accelerating you upwards (F=ma, as per Newton).

This upwards acceleration exactly counteracts your natural tendency (in an inertial frame) to plunge towards the center of the Earth in an elliptical orbit.

I would of thought it was the other way around, My backside, the seat , my carpet, the floor  is all accelerating centripetally ?


How can my settee oppose gravity and push back?







 

Offline jeffreyH

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The cushions on your sofa are not flat like pancakes and are resisting gravity. When you sit they exert a force on you that is equal and opposite to the force you exert on them.
 

Offline Thebox

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The cushions on your sofa are not flat like pancakes and are resisting gravity. When you sit they exert a force on you that is equal and opposite to the force you exert on them.

I am aware of Newton's third Law.   My cushions compress, the density compression is the resistance to the cushions becoming flat like pancakes, when I sit on the cushion, I exert a force on my cushion, the cushion exerts a force on the settee framing, the settee exerts a force on the floor, the floor exerts a force on the foundation, the foundations exert a force on the beneath, I do not see where the cushion exerts a force back when the cushions mass spreads and does not change in mass but only in form.

There is no force to make you accelerate in the opposite direction, all the force is centripetally , so I ask again how can the ground push back?


Is it not true that the only natural known push force is when there is two like positive charges?

Ok I have drew it, presently we think B, why not A and C?





« Last Edit: 07/03/2016 21:23:48 by Thebox »
 

Offline evan_au

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Quote
presently we think B, why not A and C?
(A) is not correct for someone sitting on a seat or standing on the ground, because the electrostatic forces of the electrons in the atoms of the Earth resist squashing, and produce an upward force which opposes the downwards force of gravity.
        But (A) is correct for a satellite which is about to burn up in Earth's atmosphere. There is no upward force to keep it at the same altitude, and no horizontal velocity to keep it in orbit, so it will accelerate downwards towards a fiery demise. Any pieces that reach the ground will look like (B).

(B) agreed. That is the common view.

(C) I think this is reasonable. As well as the upward force counteracting gravity, there are horizontal Van der Waals forces which prevent you sliding across the floor (unless you sketched the diagram on an ice-skating rink...)

PS: Congratulations! This must be about the most relevant and comprehensible diagram I have seen you sketch - especially if you did it on ice-skates!
 

Offline Thebox

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PS: Congratulations! This must be about the most relevant and comprehensible diagram I have seen you sketch -

Maybe now you are getting to know me you are starting to understand me better, I do not see them diagrams being different to any others I have done.



OK, thank you thus far,


This object contains positive energy?


Positive energy wants to expand always?


What holds the object together?






« Last Edit: 08/03/2016 11:30:38 by Thebox »
 

Offline jeffreyH

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The arrows in your diagrams could be considered to be vectors. Which have a magnitude and direction. This leads nicely into linear algebra.
 

Offline Thebox

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The arrows in your diagrams could be considered to be vectors. Which have a magnitude and direction. This leads nicely into linear algebra.

OK, riddle me this riddle me not lol.


in relationship to the diagram
+q=+ve

-q=-ve

in relationship to isotropic

+q=>4/3 pi r

-q=<4/3 pi r



In relationship to 0→←0
+(neg)=-ve


« Last Edit: 08/03/2016 12:54:03 by Thebox »
 

Offline Thebox

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The arrows in your diagrams could be considered to be vectors. Which have a magnitude and direction. This leads nicely into linear algebra.


X≠Y


Linear algebra using only two vectors, I said this about poker, I understand linear algebra now , I can do it in basic .



I started here in learning


https://www.khanacademy.org/math/linear-algebra/vectors_and_spaces



v(c)=[y0Y]?




I had to draw the answer did not know how to do the brackets.




U can replace 0 with N if you like.







« Last Edit: 08/03/2016 14:12:46 by Thebox »
 

Offline evan_au

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Quote from: TheBox
I started here in learning
The Khan academy is a good place to learn stuff!

Try some mathematics classes about drawing graphs. Do they have some about drawing scientific diagrams?
The most recent set of diagrams and equations has returned to the usual standard. :-\
 

Offline Thebox

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Quote from: TheBox
I started here in learning
The Khan academy is a good place to learn stuff!

Try some mathematics classes about drawing graphs. Do they have some about drawing scientific diagrams?
The most recent set of diagrams and equations has returned to the usual standard. :-\

Sorry I got carried away with Jeff mentioning linear algebra, you wouldn't relate to my diagrams this time because they are not of or like present knowledge, my apologies for slipping into my own thinking.

 

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