Would a moving scale read more than a scale at rest?

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Discussion Overview

The discussion revolves around whether a moving scale would read a different value compared to a scale at rest when measuring the mass of an object. The scope includes theoretical considerations of mass, relativity, and the implications of relativistic effects on measurement.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • One participant suggests that both the mass on the scale and the scale itself would experience an increase in mass due to their motion, questioning if this would affect the reading.
  • Another participant asserts that, according to the principle of relativity, the scale would not read any more than if both were at rest.
  • A third participant agrees with the previous point, stating that the mass is at rest relative to the scale, thus the reading remains unchanged.
  • One participant provides an example where a scale reads 1.0000 kg when at rest, arguing that running past the scale at a high velocity would not change this reading.
  • Another participant speculates that the original poster might be considering the effects of relativistic mass increase and how it could affect a spring scale, suggesting potential complications in measurement similar to those encountered in relativistic experiments.

Areas of Agreement / Disagreement

Participants express differing views on whether a moving scale would yield a different reading, with some asserting it would not change and others exploring the implications of relativistic effects. The discussion remains unresolved with multiple competing perspectives.

Contextual Notes

Participants highlight assumptions regarding the nature of mass in motion and the specific mechanics of different types of scales, indicating that certain conditions or definitions may influence the discussion.

Isaiah Gray
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Assuming there is a mass on a scale, and they move with the same velocity. I know mass increases for a moving object, but the scale's mass will also increase. So would the scale read any more than if they were both at rest?
 
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According to the scale the mass is at rest, so no the scale will not read any more.
 
Suppose the scale has a display that reads 1.0000 kg for a certain object, when you're at rest with respect to the scale (e.g. standing next to it in the laboratory). Now imagine running past the scale at 0.9c. Surely the reading is still 1.0000 kg.
 
Maybe the OP is thinking that if you run by the scale at 0.9c you would expect to observe a relativistic mass increase of the mass on the scale, the scale itself, and the Earth for that matter such that if the scale was a spring scale the indicator would shift reading due to additional compression between the mass on the scale and the Earth under the scale.

Something tells me that there may be a problem with using a spring scale here... similar to the way relativistic experiments need to exclude certain forms of clocks like pendulum clocks?
 

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