3. What is force?
• A push or pull
• Force has a size or direction
• All motion is created by force
• All forces are exerted by one object on an
another
** motion does not have to occur
4. DEFINITION OF FORCE
Force is a push or pull acting on an object which changes
or tends to change the state of the object
5. Examples for pushing and pulling
actions :
Opening the door
Lifting a bag
Kicking a ball
Pulling a drawer
Pushing a box
Pushing the table
6. How is force measured ?
• Measured in newtons
• Other units kilogram pound
• One tool to measure the force of gravity is the
spring scale
7. types of forces
• Contact force
• Noncontact force
• Friction
8. Contact force
• When one object pushes or pulls by touching
another object, the first object is applying a
contact force to the second
9. Non Contact forces
• A non contact force is any force applied to an
object by another body without any object
• Magnetic force and gravitational force are the
examples of non contact force
10. Magnetic forces
• The opposite poles of a two magnet attracts
each other without any contact . So magnetic
force is a non contact force
11. Gravitational force
• Have u wondered why the ball hit for a six by a
batsman comes back to the ground ?
• Why a mango or an apple falls to the ground ?
It is because the earth pulls them down . This
force is called the force of gravity.this is an
example for non contact force .
