What is the consequence of total internal reflection regarding light transmission?

Total internal reflection occurs when light travels from a medium with a higher refractive index to a medium with a lower refractive index, and the angle of incidence exceeds a specific critical angle. Under these conditions, instead of refracting into the second medium, all the light is reflected back into the first medium.

The crucial consequence of this phenomenon is that light remains trapped within the medium from which it is coming, rather than passing through to the second medium. This principle is widely observed in optical fibers, where light signals are kept within the fiber, allowing for efficient transmission of information over long distances.

This behavior is foundational in the design of various optical devices and technologies, as it ensures that light does not lose intensity through transmission into another medium. Thus, the statement that light remains within the medium accurately describes the result of total internal reflection.