What will show scale inside rocket?

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    Rocket Scale
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Discussion Overview

The discussion revolves around the effects of a rocket's speed relative to gravitational forces, particularly focusing on how these factors influence the readings of a scale inside the rocket. Participants explore scenarios where the rocket's speed is either less than or greater than gravitational influences, incorporating concepts from classical mechanics and gravitational theory.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant proposes that the scale inside the rocket measures the combined gravitational forces from both the Earth and the rocket, suggesting that the readings depend on the rocket's acceleration rather than its speed.
  • Another participant challenges the notion of "speed of gravity," asserting that gravitational fields are already present in space and do not have a speed in the conventional sense.
  • A different viewpoint introduces a scenario involving two masses and questions how changes in temperature and acceleration affect gravitational influence, emphasizing the need for constant acceleration in the analysis.
  • One participant expresses confusion regarding the definitions of speed and gravitation, noting that they lack compatible units for comparison.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the definitions and implications of speed versus gravitational influence. Multiple competing views remain regarding how these concepts interact and affect scale readings inside the rocket.

Contextual Notes

There are limitations regarding the definitions of "gravitation" and "speed," as well as the assumptions made about the compatibility of units for comparison. The discussion also reflects unresolved mathematical steps related to the effects of acceleration on gravitational readings.

Maciej Ma
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lab_space.jpg


I want to kindly ask about opinion what will be if :

a) rocket's speed < gravitation
b) rocket's speed > gravitation

************************************************************
Earth ----- Rocket[W]m >>> constant V
lab_ground.gif

[W]- scale can measure kg
[m]- person mass

Scale is showing Qearth + Qrocket

Qearth - gravitation between person and Earth (Newton's grav. force )
Qrocket - gravitation between person and rocket (Newton's grav. force)
*****************************************************

Rocket[W]m >>>>> constant acceleration
lab_space.jpg


Rocket[W]m ----------------> G<V< C

G - gravitation speed in Vacuum , C- light's speed

Scale is showing Af + Qrocket
Af - acceleration forces ( rocket's engine work give constant a )
Qrocket - gravitation between person and rocket ( Newton's gravitation )

Qrocket = 0 WHY ?

Mach- first engineer who described Supersonic Speed problem

( please look on 4 animations below link (left side of page )

V= zero , V>0 , V= sound , V>sound //1,4 Mach

http://www.acs.psu.edu/drussell/Demos/doppler/doppler.htmlWhat will show scale if body m is moving faster than own gravitation ?

Rocket represent mass M
Person represent mass m

M---r----m ----------> G<V

Mass M is sending (EM) waves but waves can not touch the mass m
mass m is going faster than own signals

what will show scale ?

M---r----m ----------> G<V

M---r----m ----------> V <G More better is showingbproblem below example

P1...Sun-----------Earth ------> cnstant VP1............SUN -----------Earth >>>> constant acceleration

Sun Was in past in Point 1 . Sun started gravitation signal in P1 .

Please add to above Inverted Square Law.

How big Intensity will feel Earth ? Haw far from P1 Earth will register signal that started in P1 ?

please compare 5-6 minutes ----> constant motion situation

to 5-6 minutes >>>>>>>>>>>>>>>>>>>>>>>>>>>>>cnastant acceleration situation

1930 Tolman surface brightness test
http://en.wikipedia.org/wiki/Tolman_surface_brightness_test
 
Last edited:
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Assuming that nothing on the scale changes, the only thing that will vary the reading of the scale is the acceleration (not the speed!) of the rocket relative to some nearby object in free fall. That will be true in all the cases you describe above, and is the only thing you need to know to analyze them all.

You mention the "speed of gravity" several times. There's no such thing; the gravitational field is already spread through all of space so no matter how far and fast you move, the gravitational field will already be there.

(So far there's no relativity in these problems - it's all classical mechanics)
 
m1-----r----mass M ----r-------m2 >>>>motion
.....Fire

Fire = that mass is changing temp.

m1 or m2 will feel more faster
that mass M is changing power of own gravitation ?

please imagine opposite direction <<<

please add to above model CONSTANT ACCELERATION !
( distance r = 1 meter or 1000 meters or 150 000 000 km )

how much time need light for distance r = 1m
how much time need light for distance r = 1000 m

how much time need gravitation to inform mass m 1 ,m2 about problem ?

To help You more
please imagine that m1,m2 are perpendicular to motion >>>

30 km/s ? ... 220 km/s
respect to what ? please read about TOLMAN test 1930 ? ( apparent position !)
 
Last edited:
Maciej Ma said:
I want to kindly ask about opinion what will be if :

a) rocket's speed < gravitation
b) rocket's speed > gravitation

I see you've got some answers already, but I find it hard to guess what you might even mean by a) and b) above.

Speed we can measure in units of velocity (meters/second for example). I'm not aware of any definition of "gravitation" that has compatible units.

And to compare quantites they must have compatible units.
 

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