Final answer:
The Earth can be considered a material point in large scale space studies where its size is negligible compared to distances involved, such as in orbital mechanics. However, for phenomena affected by Earth's rotation, such as gyroscopic effects and the use of Foucault pendulum, Earth's extended shape and rotation are significant and cannot be simplified.
Step-by-step explanation:
The rotation of Earth around the Sun and its rotation around its own axis are fundamental planetary motions. When studying certain physical systems or under specific conditions, the Earth can be considered as a material point. This simplification is valid when the size of Earth is negligible compared to the distances involved in the problem, for example, in the analysis of orbital mechanics or gravitational interactions over large scales in space. Under such conditions, the details of Earth's rotation around its axis are not relevant, and Earth's extension can be ignored.
However, when considering phenomena like the gyroscopic effects of Earth's rotation, precessional motion, or studying Earth's rotation using a Foucault pendulum, the planet's extended shape and rotation are significant factors that cannot be simplified to a point. In these cases, the rotation of the Earth on its axis is critical to understanding the observed effects, such as the day-night cycle, the Coriolis effect, and the precession of the equinoxes.