A teaching tape for SR-03, Rod Measurement and Simultaneity

The boost to 0.6c

Demonstrates the relativity of simultaneity and length contraction for a 10-ls rod at v = 0.6c.

Open SR-03 with these settings

Where it starts

The settings the tape begins from, under the constant set modern-si-2019. Values are the model's own, not the laboratory control's display: a radius of 5e-7 is half a micrometre.
SettingValue
Relative frame speed v/c (v)0.6
Proper length L0 (L0)10
Sphere radius R (R)1

What it changes, and what to expect

  1. Step 1

    Signature platform-simultaneous pair at v = 0.6c

    A pair simultaneous in K (dt = 0, dx = 10 ls) is not simultaneous in k (dt' = -7.5 s, dx' = 12.5 ls).

    What the author recorded that a reader should see here.
    QuantityExpectedUnder
    dtK0 smodern-si-2019
    dtk-7.5 smodern-si-2019
  2. Set Relative frame speed v/c (v) to 0.6 changes what the run starts from

    Valid frame-simultaneous measurement in K

    Endpoints simultaneous in measuring frame K give measured contracted length L = 8 ls = L0 / gamma.

    What the author recorded that a reader should see here.
    QuantityExpectedUnder
    measuredLength8 lsmodern-si-2019

These are the values the tape's author recorded, not a result this page computed. Nothing here runs the instrument. Open SR-03 with these settings: the link puts them in its form, and it calculates when you apply them. Compare what it gives you with what is recorded here. The settings travel in the link and the laboratory reads them as it loads, so without JavaScript it opens at its worked example instead.

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