Final answer:
Increasing the rotational speed of Earth would result in a decrease in its rotational period and would affect phenomena like the Coriolis effect.
Step-by-step explanation:
Increasing the rotational speed of Earth would result in a decrease in its rotational period, which is the time it takes for a complete rotation. This means that the Earth would complete one rotation faster than before. For example, a day would become shorter and there would be more days in a year. The change in rotational speed would also affect various phenomena on Earth, such as the Coriolis effect and the length of a sidereal day.