Velocity is the speed and direction of an object's motion. It is calculated as the displacement divided by the time taken, and includes both speed and direction. Some key examples include: 1) A tropical storm was moving at 60 km/h in a northwesterly direction. Its velocity was 60 km/h northwest. 2) Lisa walked 500m in 10 minutes, then jogged back in 5 minutes. Her average speed over the total 1000m distance in 15 minutes was 67 m/min. 3) Nemo swam at 12 km/h and the current was 10 km/h. His velocity was 22 km/h towards his friend's house, and only 2 km/h returning

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