3.1. The Big Idea http://www.ck12.org
3.1 The Big Idea
One dimensional motion describes objects moving in straight lines. Speed is a scalar measure of how quickly an
object is moving along this line Velocity is speed with a direction, making it a vector. If an object’s velocity changes
with time, the object is said to be accelerating. When restricted to one dimension, there are only two possible
directions for the velocity and acceleration vectors to point in. As we’ll see in the next chapters, understanding an
object’s acceleration is the key to understanding its motion.
Key Definitions
Symbols{
∆(anything) Final value - initial value
anything 0 Value at time 0Scalars
t Time in seconds, s
d=|∆x 1 |+|∆x 2 | Distance (in meters, m)
v=|v| Speed (in meters per second, m/s)Vectors
x=x(t) Position
∆x=xf−xi Displacement
vi Initial velocity
vf Final velocity
∆v=vf−vi Change in velocity
a Instantaneous accelerationMEDIA
Click image to the left for more content.Key Equations
Averages