IB Physics A5 Definitions
This page contains our IB Physics definitions for A5. By learning each one of these definitions, you will fully cover the content for IB Physics 'Galilean & special relativity'.
Angular Deviation
The angle at which the axes of one frame of reference deviate from another in a spacetime diagram
Invariant Quantities
Quantities that remain constant and do not vary between observers, including spacetime interval, proper time interval, proper length, and rest mass
Length Contraction
The phenomenon where objects appear shorter in the direction of motion when moving at high velocities relative to a stationary observer
Light Clock
A conceptual device used to illustrate time dilation, where the time taken for light to bounce between mirrors increases with the clock's velocity
Simultaneity
The concept that the simultaneity of events depends on the observer's frame of reference, meaning events that are simultaneous in one frame may not be in another
Time Dilation
The phenomenon where time appears to move slower for objects moving at higher velocities relative to a stationary observer
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