When you watch the video above, you see a horrible crash at a Nascar Race. In situations like this, the speed at which the crash took place can make the difference between life and death. This distinction can be made by finding the instantaneous velocity.
The instantaneous velocity is the velocity of an object at a single point in time. This means we do not count any acceleration that may occur, only the current speed. This can be found easily in a steady velocity example. If a graph is linear the instantaneous velocity is simply the slope of the graph.
This is important in a collision above because this is the only number affecting the other car in a collision.
1. How would you find the instantaneous velocity of a car on the freeway?
2. What tool do policemen use to find this number?