Congress has often used the Commerce Clause to justify exercising legislative power over the activities of states and their citizens, leading to significant and ongoing controversy regarding the balance of power between the federal government and the states.
Instantaneous and Average Velocity. instantaneous velocity of an object at a particular time is equal to the slope of its position vs. time graph at that time. On the other hand, the average velocity between two times is equal to the slope of the line joining the two points on the position vs. time graph.
What about the average speed according to definition 1? In this case, the distance traveled is 1000 meter so that the average speed would be (1000 m)/(50 s) = 20 m/s. This is what the speedometer would read. According to definition number 2, the average speed is the magnitude of the average velocity. Since the average velocity is zero (vector) m/s, the magnitude of this is also zero meters per second. If you want the instantaneous speed according to the definition 2, that would also be 20 m/s.