1. Velocity
• The speed and direction of an object’s
motion.
–88 km / hr southwest
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2. VELOCITY
SPEED IN A GIVEN
DIRECTION
d
V =
t direction

3. A bird flies south at
20 m/s.
• SPEED = 20 m/s
• VELOCITY = 20 m/s south

4. A tropical disturbance spotted east of the
Philippines was moving at 60 km per hour at
a Northwesterly direction and having
maximum sustained winds of 150 km/h?
What is the storm’s velocity?
Given: S= 60km/h T= 10s dir= NW
1.Formula V= d/t with dir
2.Work/Answer V= 60km/h NW

5. CONSTANT VELOCITY

6. CHANGING VELOCITY

7. COMBINING VELOCITIES
How fast will this ball move?
What factors may affect its
speed?

8. COMBINING VELOCITIES
Rowing speed
= 16 km/hr
River speed
V1(Boat) = 16 km/hr (downstream) =
V2 (river) = 10 km/hr 10 km/hr
Combined velocity: 26 km/hr

9. What is the velocity if you are
moving upstream?
Combined velocity: (V1)
16 km/hr – (V2) 10 km/hr = (CV) 6
km/hr

10. Why is the idea
of combining
velocities
important to
launching
rockets?

11. 1. A runner moving eastward covers a
distance of a 100 meters in 10 seconds.
What is his velocity?
Given: D= 100 m T= 10s dir= East
1.Formula V= d/t with dir
2.Work V= 100m/10s East
3.Answer V= 10m/s East

12. 3. Lisa is walking to a friend’s house. She walks 500m for 10
minutes, then realizes she forgot something important to
bring. She turns around, and hurries back to her house. The
walk/jog back takes her 5 minutes.
Given: Total D= 500m + 500m = 1,000m
Total T= 10min + 5 min= 15 min
T= 10 min D= 500m
D= 500m T= 5 min

13. 3. Lisa is walking to a friend’s house. She walks 500m for 10
minutes, then realizes she forgot something important to
bring. She turns around, and hurries back to her house. The
walk/jog back takes her 5 minutes.
a. What was her average speed in m/min?
Given: Total D= 500m + 500m = 1,000m
Total T= 10min + 5 min= 15min
1.Formula Ave S = total D/total T
2.Work Ave S = 1,000m/15min
3.Answer Ave S = 67 m/min

14. 4. Nelson is running around the track oval. The oval is 800m
long. He is running at a constant speed. It takes him 180 s
to complete the track and get back to where he started.
a. What is Nelson’s speed in m/s?
Given: d= 800 m t= 180 s running at constant speed

15. a. What is Nelson’s speed in m/s?
Given: d= 800 m t= 180 s running at constant speed
1. Formula S= d/t
2. Work V= 800m/180s around oval
3. Answer V= 4.44 m/s around oval
If Nelson is running at constant speed, is he also moving
at constant velocity ?
No, he is always changing direction
(running around the oval).

16. 3. Nemo is swimming his way to his best friend’s house
Crush (the turtle). Nemo is swimming at 12 km/h and the
current is moving at 10 km/hr.
a. On the way to Crush’s house, he
swims with the current. What is Nemo
Nemo’s combined velocity on
the way to Crush’s house? Current
Given: V1= 12km/h V2= 10 km/h dir= to Crush’s house
(Nemo) (current)
1.Formula CV= V1 + V2
2. Work CV= 12 km/h + 10 km/h
3. Answer CV= 22 km/h to Crush’s house

17. b. When Nemo leaves Crush’s to go home, he has to swim
against the current.
What is Nemo’s combined velocity
on the way home?
Given: V1= 12km/h V2= 10 km/h dir= Nemo’s home
1.Formula CV= V1 - V2
2. Work CV= 12 km/h - 10 km/h
3. Answer CV= 2 km/h on the way home