Читать книгу Physics I For Dummies - Steven Holzner - Страница 51

What if you keep driving 65 miles per hour forever? You achieve uniform speed in physics (also called constant speed). Uniform motion is the simplest speed variation to describe, because it never changes.

Uniform speed may be possible in the western portion of the United States, where the roads stay in straight lines for a long time and you don’t have to change your speed. But uniform speed is also possible when you drive around a circle, too. Imagine driving around a racetrack; your velocity would change (because of the constantly changing direction), but your speed could remain constant as long as you keep your gas pedal pressed down the same amount. We discuss uniform circular motion in Chapter 7, but in this chapter, we stick to motion in straight lines.