Final answer:
A radio signal reflecting off ground objects and arriving at different times denotes a delay caused by spacetime curvature near massive objects, as explained by general relativity, and must be accounted for in systems like GPS.
Step-by-step explanation:
When a radio signal reflects off objects on the ground, arriving at the destination at slightly different times, this is known as a delay caused by the curvature of spacetime in the vicinity of massive objects like the Sun. Such delays are more noticeable when signals pass near such massive objects because of the stronger gravitational field, which bends spacetime more significantly and slows the pace of time according to Einstein's general theory of relativity. Notable practical applications like the Global Positioning System (GPS) must account for similar effects of time dilation to maintain accurate positioning data.