AST201H1 Lecture Notes - Lecture 2: Length Contraction

• School: UTSG
• Department: Astronomy & Astrophysics
• Course: AST201H1
• Professor: Bryan Gaensler

Document Summary

Ineria reference frame, no way to tell whether you"re sill or moving technically you cannot tell whether it"s you moving or whatever is under you moving. Einstein realized that we could only measure moion relaive to a given frame of reference. Speed/velocity is always relaive, i. e. both people are right relaive to where they see the movement. But the speed of light (c) is the same for everything. Naturally nothing can go faster than the speed of light. Light always travels at c (in a vacuum) No object with mass can ever reach or exceed c. No mater what reference frame you"re in, light always moves at the same speed for all. There can be disagreements about everything else, essenially everything but the speed of light is relaive. So in an example with the ball being rolled down a moving plane, diferent frames of reference give you diferent speeds, but light in this case is always idenical to all.