What is FORCE?

FORCE Basically, it is a push or pull

acting upon an object as a result of its interaction with another object.

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

What can FORCE do to MOTION?

Net force Also known as resultant force. A single force that acts and

causes a change in the state of motion of an object.

Balanced Forces net force = 0 No changes in

the state of motion are produced.

F1 = F2 = 0

Unbalanced Forces net force ≠ 0 produces

acceleration F1 ≠ F2 ≠ 0

Balanced Force vs. Unbalanced Force

Types of FORCES

Contact Forces

Exist when two objects are in contact with each other.

Types of Contact Forces

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.

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

contact.

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

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

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

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

Non-Contact Forces

Exist even when there is no direct contact between two objects.

Types of Non-Contact

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

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

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

objects

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.

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