1. Technological World
Movements & Forces

2. Types of Movements

3. Types of Motion Rectilinear motion Ex. A skateboard
Scientists believe that all motion is a combination of the following four simple types:
Rectilinear motion
Ex. A skateboard
Alternating motion Ex. A trumpet piston
Circular motion
Ex. Ex. A carrousel or Ferris wheel
Oscillatory motion (back & forth around a central point)
Ex. A swing

5. Triggering and Slowing Down of a Motion
A movement can not be triggered on its own - a force must provoke it
Ex. You must pedal a bike in order to trigger the motion
Friction of the air, the moving parts, or contact with the ground can slow down an object
Ex. Wind, you stop pedaling or brake, or friction with ground to the tire

6. Pedaling triggers motion

7. Triggering and Slowing Down of a Motion
The type of ground is an important factor in the movement of an object
Ex. It's much harder to pedal on surfaces like grass or sand than on asphalt
The friction force is greater on the grass and the sand, so you have to apply a greater force to fight the friction

8. Friction causes the bicycle to brake
The force affecting the bicycle
Is much greater on the grass
than it is on asphalt

9. Triggering and Slowing Down of a Motion
The shape of an object is also an important factor in the movement of an object
The more an object has a square shape, the more the resistance of the air causes friction
Ex. Air resistance is greater for a bus than a car with an aerodynamic profile
Aerodynamic Profile: A form that offers the least possible resistance to air

11. Effects of a Force

12. Types of Forces When you exert a force on an object, you can:
put it in motion or change its motion
deform or break it
The most common types of forces are:
Bending (flexion) force
The tension force
The compression force
The torsion force
Shearing force

13. Types of Forces Bending (Flexion) Force Tension Force
Compression Force
Torsion Force
Shearing Force

14. Simple Machines

15. Simple Machines
Simple machines are found in many objects that are part of your daily life
They can lift objects or facilitate their movement
There are 5 types of SIMPLE MACHINES
The lever
The inclined plane
The pulley
The wedge
Wheels and axles

17. Simple Machines Simple machines have 3 primary functions:
They transmit forces
They change the direction of a force
They change the intensity (size) of a force

18. The Lever
A lever has three components: the pivot (fulcrum), the load and the force
In a lever, a moving part rests on the pivot (fulcrum)
At one end of the moving part is the load (the object to be lifted or moved)
A force is applied to the other end of the moving part

20. The Lever
By moving the pivot, the load or the force, we obtain three types of levers:
The First Class Lever: The pivot is located between the force and the load (for work that requires strength or precision)
Ex. A pair of scissors

21. First Class Lever
LOAD
FORCE
FULCRUM

22. The Lever
The Second Class Lever: The load is between the force and the pivot
It always exerts a greater force on the load than the force applied
Ex. A wheelbarrow

23. Second Class Lever
LOAD
FULCRUM
FORCE

24. The Lever
The Third Class Lever: The force is exerted between the pivot and the load (to multiply the speed, the distance and the precision)
Ex. A hockey stick

25. Third Class Lever
LOAD
FULCRUM
FORCE

26. BOTTLE OPENER
HAMMER
SCREW DRIVER

27. The Inclined Plane An inclined plane has a slope
Slope reduces the amount of force required to lift a load or object
Instead of lifting an object, it is pushed
When the slope is gradual, it is easier to climb, but the distance to travel is longer
When the slope is steep, it is more difficult to climb, but the distance to travel is shorter

28. DISTANCE COVERED
DISTANCE COVERED
HEIGHT
HEIGHT
GRADUAL SLOPE
STEEP SLOPE

29. The Pulley A pulley is composed of a wheel with a rope or chain
The rope or chain fits into the groove of the wheel
The pulley helps us lift loads
There are 2 types of pulleys:
FIXED
MOVEABLE

30. The Fixed Pulley
Fixed pulley: Does not diminish the force needed to perform a job
It only allows to change the direction of the force
Ex. VENETIAN BLINDS
FIXED PULLEY
MOVEABLE PULLEY

31. The Movable Pulley
Moveable pulley: Decreases the force required (1/2) to perform a job
One end of the rope is attached to the ceiling
Load and pulley move in the same direction
FIXED PULLEY
MOVEABLE PULLEY

32. Pulley Combination
We can combine several moving pulleys to further reduce the necessary force
We can also combine a fixed pulley and a movable pulley (a hoist) to change the direction and decrease the necessary force

33. The Wedge The Wedge is a triangular prism
It is used to exert a force on an object
The wedge helps us to separate pieces
Ex. An axe OR the end of a nail
The wedge helps us lift objects
Ex. A corner to lift a piece of furniture

34. AN AXE
THE EDGE OF A NAIL
TO WEDGE AND MOVE FURNITURE

35. The Wheel & Axle Wheels and axles are used to push objects more easily
Ex. A cart to push a box more easily than on the ground
Ex. The wheels of a bicycle or automobile

36. The Transmission of Motion

37. The Transmission of Motion
Simple machines can be combined to form mechanical systems
These systems are used to transmit a movement from one object to another, through different mechanisms
The mechanisms transmit the four types of movement:
1) Rectilinear
2) Alternative
3) Circular
4) Oscillatory

40. CHAIN & SPROCKET
BELT & PULLEY

41. GEARS

42. FRICTION GEARS
PULLEY

43. The Transformation of Motion

44. The Transformation of Motion
Some mechanisms move from one type of movement to another (transform a movement)
EX. Translational to Rotational OR
Rotational to Translational

46. CONNECTING ROD & CRANK

47. CAM & FOLLOWER

48. RACK & PINION

49. SCREW & NUT