Forces were investigated in relation to how they affect an object's motion. There are two types of forces - contact forces which require touching objects, like applied force, friction, normal force and tension, and non-contact forces which act over a distance without touching, like gravitational and magnetic forces. Balanced forces are equal in magnitude but opposite in direction and do not cause changes in motion, while unbalanced forces cause changes in motion and are not equal or opposite. The net or resultant force is the sum of all the individual forces acting on an object.

1. Quarter1:Module1/Week1(S8FE-Ia-15)
MELC: Investigate the relationship between the amount of
force applied and the mass of the object to the amount of
change in the object’s motion
Pangasinan National High School
8 SCIENCE
Online Distance
Learning
Forces
MR.RONNIEM.ABSALON,JR.
Gr.8-ScienceT
eacher

3. • Identify what forces are acting on an object.
Objectives:
• Explain the effect of balanced & unbalanced
forces on the state of motion of an object.

4. FORCE
What is a

5. FORCE

6. FORCE
can be describe in
terms of what it does

7. However, forces do not always cause
motion.
Examples:
FORCE
FORCE
It does not
necessarily
follow that
force acting on
an object will
always cause
it to move.

8. DISPLACEMENT
VELOCITY
ACCELERATION

9. When a car starts moving, it speeds up. When a car nears a
stop sign, it slows down.
The car is covering different displacements at equal time
intervals, hence it is not moving in constant velocity.
Displacement
REVIEW
This means the car is ACCELERATING.

10. Direction: Examine the ball on top of the
table. Choose the letter of your answer to
the given conditions.

11. Direction: Examine the ball on top of the
table. Choose the letter of your answer to
the given conditions.

12. FORCE is a push or pull acting upon an object as a
result of its interaction with another object.
Be familiar with the following terms:
• Magnitude
• Direction
• Point of application
• Line of action

13. Be familiar with the following terms:
• Magnitude - refers to the size or strength of the force. It is
commonly expressed in Newton (N) for Meter-Kilogram-Second
(MKS) system, Dyne (dyn) for Centimeter–Gram–Second (CGS)
system and pounds (lbs) for Foot– Pound–Second (FPS) system.
In the International System of Units (SI), Newton is commonly
used which is named after SIR ISAAC NEWTON, an English
physicist and mathematician.
• Direction - points to where the object goes. The direction of the
arrowhead indicates the direction of the force. The length of the
arrow represents the amount of force (relative magnitude).

14. Be familiar with the following terms:
• Point of application - the location of where the force is applied.
• Line of action - is the straight line passing through the point
of application and is parallel to the direction of force.

15. There are two types of force, namely:
CONTACT
FORCES
Applied
Friction
Normal
Tension
NON-CONTACT
FORCES
Gravitational
Magnetic

16. CONTACT
FORCES
Applied
Friction
Normal
Tension
- are forces where objects
touch or contact with each
other.

17. CONTACT
FORCES
Applied
Friction
Normal
Tension
– a force given to a person or object
by another person or object.

18. CONTACT
FORCES
Applied
Friction
Normal
Tension
-is the force acting against or
opposite to an object in contact
with which makes the movement of
the object slow down.
FG
Fai
r

19. CONTACT
FORCES
Applied
Friction
Normal
Tension
-is the force that acts
perpendicular to the surface of the
object in contact with.

20. CONTACT
FORCES
Applied
Friction
Normal
Tension -is the force applied to string, rope,
chain or cable.

21. Normal Force = Gravitational Force
Remember
CONTACT
FORCES
Applied
Friction
Normal
Tension
NON-CONTACT
FORCES
Gravitational
Magnetic

22. NON-CONTACT
FORCES
Gravitational
Magnetic
- are forces where objects
do not touch or contact with
each other. These forces act
over a zone or area called
FIELD.

23. NON-CONTACT
FORCES
Gravitational
Magnetic
- is the force of attraction between
two objects.
Moon
Eart
h
Meteor

24. NON-CONTACT
FORCES
Gravitational
Magnetic
- it is the force exerted on a field of
attraction or repulsion as in the
case of magnets and other
magnetic materials.
N
S

25. Balanced Forces & Unbalanced Forces
To describe these forces you must
know two things:
1. Magnitude -the amount of force
2. Direction of the force

26. Balanced Forces VS Unbalanced Forces
Forces that are equal in magnitude but
opposite in direction are called balanced
forces. Balanced forces do not cause a change
in motion. When balanced forces act on an
object at rest, the object will not move.

27. Balanced Forces VS Unbalanced Forces
Forces that cause a change in the
motion of an object are unbalanced
forces. Unbalanced forces are not
equal magnitude and opposite
direction.

28. In an object, there may be several
forces acting on it. Net force or
resultant force is the sum of all
forces acting on an object. Two or
more forces in the same line of
action exerted on an object are
balanced if their effects cancel each
other.
Net or Resultant Force
Net Force =0 Net Force= -100 N
+
- +
-

29. PerformtheActivitieson
thisModule
pages 11-14

30. 1. Any push or pull is called ________________.
2. ________________ refers to the size or strength of the force while
________________ points to where the object goes.
3. There are two types of forces, namely ________________ and ______________.
4. Applied, friction, normal and tensional forces are examples of
________________ forces.
5. Gravitational and magnetic forces are examples of _______________ forces.
6. __________ are forces that are equal in magnitude but opposite in
direction.
9. If the forces in an object are balanced, the net force is _____________.
7. ___________ are forces that cause a change in the motion of an object.
8. The sum of all forces acting in an object is called ________________.
10. If the forces in an object are unbalanced, the net force is
______________.
Fill in the blanks with correct word/s. Write your answers on
a separate sheet of paper.
Force
Magnitude
Direction
Contact
Non- contact
Balanced
Unbalanced
Net or resultant force
Zero
Not zero

31. 1. Any push or pull is called ________________.
2. ________________ refers to the size or strength of the force while
________________ points to where the object goes.
3. There are two types of forces, namely ________________ and ______________.
4. Applied, friction, normal and tensional forces are examples of
________________ forces.
5. Gravitational and magnetic forces are examples of _______________ forces.
6. __________ are forces that are equal in magnitude but opposite in
direction.
9. If the forces in an object are balanced, the net force is _____________.
7. ___________ are forces that cause a change in the motion of an object.
8. The sum of all forces acting in an object is called ________________.
10. If the forces in an object are unbalanced, the net force is
______________.
Fill in the blanks with correct word/s. Write your answers on
a separate sheet of paper.
force
Magnitude
direction
contact
non- contact
Balanced
Unbalanced
net or resultant force
zero
not zero
contact non- contact
A
n
s
w
e
r
s

32. Thank you!

33. References:
https://www.google.com/search?q=chandelier&tbm=isch&hl=en&safe=active&tbs=sur:fm&chips=q:chand
elier,g_1:dining+room:KpyWgTBoZAY%3D&safe=active&hl=en&sa=X&ved=2ahUKEwjZ48bauaLrAhUA
y4sBHdSIDFcQ4lYoA3oECAEQHA&biw=1349&bih=657#imgrc=SGE0MsMXn3AhNM
https://www.google.com/search?q=holding+hands&tbm=isch&hl=en&safe=active&chips=q:holding+hand
s,g_1:heart:bnM3RtjwB_8%3D&tbs=sur:fm&safe=active&hl=en&sa=X&ved=2ahUKEwiw-
9feqKLrAhUOhZQKHY_CD0QQ3VZ6BAgBEBk&biw=1349&bih=657#imgrc=c2nxNWdE9ucS_M
Ppt THE CONCEPT OF FORCE by Sir Randy B. Cayabyab, Basista NHS
Science Quarter 1 – Module 1: Forces