Rocket Your Way Through SACE Stage 2 Physics 2025 – Unleash Your Inner Einstein!

One of the key postulates of special relativity is that the speed of light in a vacuum is an absolute constant, meaning it does not change regardless of the motion of the observer or the source of light. This postulate is foundational to Einstein's theory and leads to many of the counterintuitive conclusions that arise in the realm of high speeds and relativistic physics.

The constancy of the speed of light has profound implications for our understanding of space and time, including the interrelation of time dilation and length contraction. It establishes that all observers, no matter their relative velocities, will measure the same speed of light, which is approximately 299,792 kilometers per second. This principle is crucial as it allows for the formulation of the equations of special relativity, which describe how time and space are perceived differently by observers in different inertial frames of reference.

In contrast, light does indeed travel at different speeds in different mediums, such as water or glass, but this scenario does not apply in a vacuum, where the speed of light is strictly constant. The notion that light could exceed the speed of sound or that its speed is dependent on gravity are outside the framework established by special relativity, as the speed of light remains constant regardless of these