Chapter 2 of the Pearson Physics textbook by James S. Walker
Chapter 2.1
In physics a frame of reference is referred to as a coordinate system
Distance is the total length travelled and the SI unit is meter (m)
Displacement - Change in an object’s position
Displacement and Distance are not the same, for example:
You could have travelled 10 miles and travelled another 10 miles back and your displacement would be 0 meanwhile your total distance travelled would be 20 miles.
That isn’t to say that displacement and distance cannot be the same, if you travel 10 miles in a straight line then the total distance travelled and displacement would be the same
Chapter 2.2
Speed describes how fast or slow something moves
Average Speed - Speed of an object defined over a given period of time
SI unit for speed: meters per second (m/s)
Average velocity is the displacement per unit of time
average velocity =
Average velocity also indicates the direction that the object was traveling on average
Average Speed and Average Velocity are not the same
Speed:
- Rate of motion
- Always positive
- The greater the speed of an object the faster it moves
Velocity:
- Gives rate of motion and direction
- Sign of velocity indicates direction
- Magnitude of velocity is the speed of motion
Chapter 2.4
SI unit position: m
Equation for constant velocity is a straight line