1. What measurements do we use to describe the world around us?
Time & Distance
Key Question:
What measurements do we use to describe the world around us?

2. How do we use time? 1.To determine time of day
2.To determine the amount of time between two moments

3. What is the difference between accuracy, precision, and resolution?
Accuracy – Correct in all detail.
Precision - trying to specify details exactly
Resolution – The degree of visible detail

4. Why are accurate measurements of time necessary?
To determine the actual amount of time between two moments.
What units are used to measure time?
Second, minute, hour, day, week, month, year, etc.

5. What is speed?
The rate at which something moves.

6. How do we measure and communicate length and position?
Use a ruler or other measuring device.
The main units we will use are: kilometers, meters, centimeters, & millimeters

7. What are the factors that affect the speed of a car rolling down a hill?
Distance allowed to roll before measure speed.
Distance over which speed is measured
Weight
Angle of the slope
Friction

8. How is speed measured? Speed = Distance ÷ Time v = d/t d = vt t = d/v
Velocity = the speed of something in a given direction

9. Copy this graph into your notes and describe what is happening.

10. What's happening in this Graph?
In the first 5 seconds how far did the person travel?
How far did the person move in the next 10 seconds?
How far did the person move in the last 15 seconds?
4 m
0 m
7 m
What was the person’s average speed from:
time = 0 s to time = 5 s
time = 15 s to time = 30 s
time = 0 s to time = 30 s
0.8 m/s
0.47 m/s
0.37 m/s

11. What measurements do we use to describe the world around us?