Final answer:
The rate of tectonic plate motion is generally quite slow, moving roughly at the pace of growing hair which is around 4-5 cm per year. However, minor differences in these rates can result in significant geographical differences over long geological timescales.
Step-by-step explanation:
Based on the information presented in the question, the rate of tectonic plate motion appears to be quite slow. For instance, we've observed the North American Plate moving at a rate equivalent to the speed at which hair grows, which is about 4 to 5 cm per year. This rate translates into an incredibly small distance (around 1.3 × 10-⁹ m) per second. In terms of kilometers per million years, the speed is approximately 4.0 × 10¹ km/my. It's essential to understand that while these measurements may seem insignificant in our daily lives, they have huge effects over geological timescales. For instance, the Yellowstone and Anahim hotspots show distinct rates of plate motion, indicating that North America is not a rigid tectonic block, and that different sections move at slightly different speeds.
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