Answer: light can transmitted through long fiber optic strand as a result of total internal reflection
Explanation:
Total internal reflection occur when a right ray incident at the interface of two less dense media is completely reflected back to a denser medium, as a result of a greater angle than the critical angle.
Optical fibers use total internal reflection to transmit light. Light passing through the inner core of the optical fiber strand is reflected back rather than being refracted to the cladding.
Note: the optic fiber is made of dense solid glass core (the inner) surrounded by less dense cladding (outer)