Introduction to Free Fall and Circular Motion for ESL learners at international schools, simple definitions with questions, examples and gifs.

1. Friction&
Gravity
What is Friction?
Name the different types?
What’s Gravity?
What two factors affect Gravity?
What’s the difference between
Weight & Mass?

2. Free Fall & Circular Motion

3. Introduction
What is Free Fall?
What are Satellites?
How do they stay in Orbit?

4. Find&Circle
Find the following words:
1: Cause 2: Independently
3: Effect 4: Satellite
5: Free Fall 6. Centripetal
Force

5. WorkinPairs!
Try to define the words you have
circled by reading the passages &
thinking about what each word
might mean.

6. FreeFall

7. FreeFall
The motion where the acceleration
is caused by Gravity.
Therefore the only Force acting on
an object is:
Gravity

8. FreeFall
Lets Sky Dive!
https://www.youtube.com/watch?v=
e7mSAvR_DUc

9. FreeFall
And the Force of Gravity causes
the object to accelerate.
 Fluid Friction from the air around the
object that is falling.
 Friction acts against gravity reducing
the acceleration.
 If it falls long enough the acceleration
becomes zero while the velocity of the
falling object becomes constant.

11. FreeFall

12. Acceleration
dueto Gravity
As something falls it acquires
acceleration.
The Acceleration due to Gravity is
9.8 m/s2
The Speed of Gravity = 9.8 m/s
EVERY SECOND!
Example After 3 Seconds, Speed
is (9.8m/s)(3) = 29.4 m/s.

13. Horizontal&
Vertical.
Horizontal – Straight line
ACROSS, Left to Right. East to
West etc.
Vertical – Straight line UP/DOWN,
North to South.

14. Whichisthis?

15. Andthis?

16. Concept
Checking
Questions
What is Free Fall?
Acceleration caused by Gravity.
What is the Acceleration due to
Gravity?
9.8m/s2
What is the difference between
Vertical and Horizontal lines?

17. SatelliteMotion
Curved path matches curved surface
of Earth.
Continuously fall toward Earth but
Earth is curved so they travel around
it.
Gravity continuously changes the
satellite’s direction.

18. SatelliteMotion

20. Centripetal
Force
A force which causes an object to move
in a circular path.
An object travelling in a circle is
accelerating because its constantly
changing direction.
 Therefore a Force must be acting on it.

22. Centripetal
Force
The force ALWAYS points toward
the centre of the circle an object is
moving in.
 Therefore with satellites gravity
makes the centripetal force!

23. Experiment Time!
https://www.yout
ube.com/watch?v
=qgreqhzkayY
Marble
Wine Glass
Positive Attitude
And great music!
https://www.youtube.com/watch?v=
PGNiXGX2nLU

24. Concept
Checking
Questions
What is Satellite Motion?
Curved path matches curved
surface of Earth.
What is Centripetal Force?
A force which causes an object to
move in a circular path.

25. Worksheets!
Thank youfor
today!