1. Chapter 15: Motion & Momentum Section 1: What is motion?
By: Tashin B.

2. Aim: What is motion. Do Now: Define motion
Aim: What is motion? Do Now: Define motion. Motion is change of location or position of an object with respect to time.

3. Motion Motion occurs when an object changes its position.
An object changes position relative to a reference point.
Both Distance and Time are important in describing motion.
Sometimes you know motion has occurred even if you didn’t see it happen.
Relative Motion:- you are moving even when you are sitting in your chair. You are moving relative to the other planets.

4. Example of motion

5. Distance And Displacement
Distance: is the total length that you have moved between two points.
The SI unit of length or distance is the meter (m). Longer distances are measured in kilometers (km).
Displacement: is how far and in what direction an object has moved from its start position.

6. Speed
Speed is the distance an object travels in a given amount of time.
Speed = distance
time
Metric units used to measure speed:
m/s (meters per second)
km/hr (kilometers per hours)
mph (miles per hour)
An object in motion can change speeds many times as it moves from one point to another, speeding up or slowing down.

7. Types of Speeds
Average speed: is the total distance traveled divided by total time taken.
Average speed: total distance
total time
Instantaneous speed: speed at any given moment.
Constant speed: when speed doesn’t change.

8. Graphing Motion
Motion can be graphed on a distance-time graph with time plotted on the horizontal axis and distance plotted on the vertical axis.
The steeper the line on a distance-time graph, the greater the speed.
A horizontal line on a distance-time graph indicates that no change in position is occurring and the speed is zero.

9. Example of a Motion Graph

10. Velocity
Velocity- is the speed of an object and its direction of motion; velocity changes if either, or both, of these changes.

11. Questions What are the two important factors of describing motion?
Time and Distance
2. What is constant speed?
Constant speed is when speed doesn’t change.
3. What is speed? And how is it calculated?
Speed is the distance an object travels in a given amount of time. Speed= distance/time.
4. Is Speed and velocity the same? Why or Why not?
No. Speed deals with the rate at which an object travels and velocity deals with the rate at which that object changes its position.