3. FORCE
Basically, it is a push or pull
acting upon an object as a
result of its interaction with
another object.

5. FORCE
But in Physics, it is a quantity
that may change the state of
motion of an object.
SI unit is newton (N): 1N = 1
kg.m/s2

7. What can FORCE do to
MOTION?

10. Net force
Also known as resultant force.
A single force that acts and
causes a change in the state
of motion of an object.

11. Balanced Forces
 net force = 0
 No changes in
the state of
motion are
produced.
 F1 = F2 = 0

12. Unbalanced Forces
 net force ≠ 0
 produces
acceleration
 F1 ≠ F2 ≠ 0

13. Balanced Force vs. Unbalanced
Force

14. Types of FORCES

15. Contact Forces
 Exist when two objects are in
contact with each other.

16. Types of Contact Forces

17. 1. Applied Force (Fapp)
 A force applied to an object by
another object or by a person.
 The direction of the applied force
depends on how the force is applied.

18. 2. Normal Force (N)
 support force
 A force perpendicular to the surface of
contact.

19. 3. Air Resistance Force
(Fair)
 special type of frictional force which acts
upon objects as they travel through the
air
 always opposes the motion of the object

20. 4. Tensional Force
(T)
 the force transmitted
through a string rope or
wire when it is pulled
tight by forces acting at
each end
 the direction is always
away from the object

21. 5. Spring Force (Fspring)
 the force exerted by a
compressed or stretched
spring upon any object
which is attached to it
 first studied by Robert
Hooke

22. 6. Frictional Force (f)
 force exerted by a surface
as an object moves across
it or makes an effort to
move across it.
 opposes the motion of the
object
 always acts parallel to the
surface in contact and
opposite the direction of
motion

23. Non-Contact Forces
 Exist even when there is no direct
contact between two objects.

24. Types of Non-Contact

25. 1. Gravitational Force
 also known as Weight (W)
 W = mg: m = mass, g = acceleration
due to gravity, 9.8 m/s2
 the force with which the Earth, moon
or other massive body attracts an
object towards itself

26. 2. Electrical Force
 force that exists between charges
 attractive or repulsive

27. 3. Magnetic Force
 force that exists in magnets
 makes magnets attract or repel
objects

29. Synthesis
 Concept Map:
Create your own concept map about the
different ideas on force based from
discussion and activity.
 Journal Entry:
 What is force? Explain the nature of
force.
 Explain how balanced and unbalanced
forces are related to motion.

30. Assignment
 Study for a quiz on Thursday. Topic:
Types of Forces
 Study in advance the topic FRICTION.
 (LAB GROUP) Bring the following on
June 27, Monday
- pingpong ball, small marble, basketball
ball
- drinking glass
- 1 peso coins
- drinking straw