1. Roller Coaster Physics
Speed & Velocity

2. What’s the difference between Speed and Velocity?

3. Speed vs. Velocity Speed: Velocity:
The measure of how fast an object is moving
Measured as distance traveled per unit of time
Example: The car was going 75 miles per hour (mph)
Velocity:
Speed with direction
Measured as distance traveled per unit of time AND direction
Example: The car was going 75 miles per hour north

4. Speed =
distance
time
Velocity =
distance
time
south

5. Answer: His velocity was 16 km / hour
A windsurfer travelled 28 km in 1 hour 45 mins.
Calculate his velocity.
Distance
Time
Velocity = 28
1.75 =
1 hour 45 mins
= 16 km/h
Answer: His velocity was 16 km / hour

6. Calculating *Velocity for the project
Measure distance the object traveled
Measure the time it took the object to travel distance
Use the velocity formula:
Remember all velocity measurements should be in cm/s
* This is an average velocity for the distance being measured
Velocity =
Distance (cm)
Time (s)

7. Practice: Calculate average speed
Distance: 150 m
Time: 5 seconds
Velocity: distance / time
150 m
30 m/s

8. Velocity Mini Lab 1 100 cm 2 100 cm 3 100 cm 4 100 cm 5 100 cm Trial #
Distance (cm)
Time (sec)
Velocity (cm/s) 1
100 cm 2
100 cm 3
100 cm 4
100 cm 5
100 cm

9. Velocity Mini Lab
You’re going to practice calculating the speed of a rolling marble.
Partner up with someone you have not worked with yet
Each pair will grab the following:
Piece of wood & index card
Marble (1 x each size)
Meter stick
Stopwatch
You will set up a ramp and measure a full meter
Roll the marble down the ramp and time how long it takes to go a meter
Collect your data