Alexander Fufaev

Formula: Length Contraction

Length contraction: distance of two planets from the reference frame of the resting earth

Length / Distance

Unit
Length of the body (e.g. a rod) measured by an observer moving relative to this body with velocity \( v \). But it can also simply be the spatial distance between two objects.

Rest length

Unit
Length at rest is the length of a body measured by an observer when the observer is in the body's rest frame. That is, from the observer's point of view, the body is not moving.

Relative velocity

Unit
Relative velocity between the observer and the body.

Speed of light

Unit
Speed of light is a physical constant and indicates how fast light travels in empty space (vacuum). It has the following exact value in vacuum: $$ c ~=~ 299 \, 792 \, 458 \, \frac{ \mathrm{m} }{ \mathrm{s} } $$