Zusammenfassung der Ressource
Science Physics Chapter One
- Lesson 1 Describing Motion
- An object is in motion if its position changes relative to another object.
- The place or object used for comparing
motion is known as the reference point
- Motion can change relative to different objects
- ex.) If you use your chair as a reference point you may not be moving. But if you
use the sun as a reference point your moving extremely fast.
- To describe motion you need to use proper units of measurement
- Scientists use the International System of Units (SI) for measurements
- The SI unit for length is meters.
- Distance is the length of a path between two points
- Lesson 2 Speed and Velocity
- The speed of an object is the distance an object travels per unit of time
- To calculate the speed of an object, divide the distance the object the amount of time it takes to travel that distance
- Speed=Distance÷time
- The SI unit for speed is m/s
- To calculate average speed, divide the total difference travelled by the total time.
- Instantaneous speed is the speed at which an object is moving at a given instant in time.
- Speed in a given direction is called velocity.
- You can show the motion of an object on a line graph in which you plot distance versus time.
- Time is shown on the x-axis and distance is shown on the y-axis.
- The steepness of a line on a graph is called slope.
- The slope tells you how fast one variable changes in
relation to the other variable in the graph
- Since speed is the rate that distance changes in relation to
time, the slope of a distance vs time graph represents speed
- You can calculate the slope of a line by dividing the rise by the run
- Rise is the vertical distance between any two points on a line
- Run is the horizontal difference