2. What is Speed?
Speed: The ratio of the distance an object moves to the amount of time an object moves Average Speed: Speed over the course of the ENTIRE trip (with different speeds throughout) Instantaneous Speed: Speed at a particular point in time. Ex: Reading your speedometer

3. Speed vs. Velocity Very similar, except velocity has direction
Both have same number
EX: 55 mph is a speed. The velocity would be mph EAST

4. Average Speed Example
If Joe drives 300 miles for 5 hours, what is his average speed in mph (miles per hour)?
Miles / Hour
300 Miles/ 5 Hours
We want per 1 hour (not 5) , so how do we get that?
What was his average speed?
60 mph

5. Average Speed Example
If Fabian drives 300 miles for 5 hours, what is his average speed in mph (miles per hour)?
Miles / Hour
300 Miles/ 5 Hours
We want per 1 hour (not 5) , so how do we get that?
What was his average speed?
60 mph

6. Speed Equation
V= d/t
V= speed/velocity
d= distance
t= time

7. Answer: His speed was 16 km / hour
A windsurfer travelled 28 km in 1.75 hours.
Calculate his speed. Use FSA! D T
V =
Formula
Distance
Time
Speed =
28km
1.75h =
Substitution
= 16 km/h
Answer: His speed was 16 km / hour
Answer

8. Toy Train Speed Problem

9. Answer: He travelled 125 km
A bus travelled at an average speed of 50 km/h for 2.5 hours.
How far did it travel? FSA!!! D T
V =
Need to do a little math here to get “d” by itself
Distance
Time
Speed =
50 km/h= d
2.5 hr
50 km/h x 2.5 hr= d
= 125 km
Answer: He travelled 125 km

10. Answer: It took 9 hours 15 minutes
A train travelled 555 miles at an average speed of 60 mph. How long did the journey take? FSA!!! D T
V =
555 mi
60mi/h =
60mi/h x t =
555 mi t
555 mi
60mi/h = t
= hours
= 9 hours 15 mins
Answer: It took 9 hours 15 minutes

11. 2 options-always use v=d/t and solve using cross-multiplying/dividing
In speed word problems, you will be asked to solve for either speed, distance, or time.
2 options-always use v=d/t and solve using
cross-multiplying/dividing
OR use these (more memorization):
Speed =
Distance
Time
Time =
Distance
Speed
Distance =
Speed x
Time