MACHINES

What are machines?

• Any object, no matter how simple, that helps us complete a task in a faster, simpler, and more comfortable way

Types of Machines

• SIMPLE– Formed by 1 or a few pieces

• COMPLEX– Formed by many different pieces

Types of Machines and types of energy

• Machines use different types of energy to work– Energy from a person doing work– Wind– Water– Electricity

SIMPLE MACHINES

• WHEEL: helps move weights and reduces the force that a person needs to exert

• PULLEY: Changes the direction of a moving object when you apply force and helps lift objects

• INCLINED PLANED: Lessens the force that someone has to apply when trying to lift or move an object. The bigger the plane the less force the person has to put in.

• LEVER: Intensifies the strength that a person applies

Machines and their uses: why do we use machines?

• To do work in less time• To save one’s strength• To do dangerous work• To transform energy from one type to another

Machines• Let us move and carry heavy objects.

Machines themselves also produce movement.– Examples: Wheelbarrows, planes, fan

• Manual Machines: People put in a portion of the force needed

• Automatic Machines: We employ electricity to do the work of people

Thermal Machines

• Machines we use to heat or cool.– Examples: Stove, Heater, Refrigerator

Machines we use to communicate and obtain information

• Cameras, video cameras, and tape recorders: let us capture still or moving images

• GPS: To figure out where we are and where we are going

• Videogame consoles and computers: They are used to play, write, find information, go on the internet, and communicate with each other

PARTS OF A MACHINE

• Structure and Case: The structure is how the parts of the machine connect to each other while the case protects the machine

• Motor: What allows an automatic machine to produce movement

• Mechanical Operator: Transmits the movement from the motor to the other parts of the machine

• Electrical Circuits: They are in the machines that use electricity or batteries. They move the energy to all parts of the machine. Electrical circuits are made of very small pieces, such as chips

PARTS OF A MACHINE• Sensors: Receives information from the inside

or outside of the machine– Thermometer Radiator– Light Elevator– Infrared TV remote– Movement Light

• Signs and Display Screens: Shows information about how to work or use the same machine– Speed limits– Temperature– Elevators: floors, going up or going down

SIMPLE MACHINES

• A moving machine that changes the direction or strength of a force and also transmits movement– Wheels: Smooth or jagged– Axel: Is connected to the wheel and turn in the same

direction– Cord: Passes the movement from one wheel to another– Levers: Can either strengthen or weaken the force needed

SIMPLE MACHINES• Springs: Accumulate energy• Handles: Starts movement in manual

machines• Zippers: Rugged pieces with teeth that

connect with other rugged pieces (such as another zipper or wheel)

Wheel and Axle

• A machine formed by two parts that rotate together and transfer force from one to another

COG WHEEL• Machines formed by 2 or more pieces that fit

together. The pieces that fit together are called “teeth”

• When each piece has the same number of “teeth” they turn at the same speed, when they have a different number of “teeth” the smaller piece turns faster

ZIPPERS

• Convert a circular movement into a linear movement

Gear Shift

• Gears that are used to change the speed of a wheel, such as on a car or bicycle.

Technical Advances and Society

• Change in the way that people work– Tasks are easier and tire us less– Machines do work that people used to: could that also have

negative consequences? What are they?– Electronic Information: Computers, faxes, printers, internet

• Changes in transportation– Many options for daily transportation: Cars, buses, trams – Planes: Getting you from one place to another faster– Importing\Exporting Merchandise: Sending goods out by boat

and plane– The use of fossil fuel: leads to GLOBAL WARMING

Technical Advances and Society• Changes in health

– Medicines, vaccines– Organ Transplants– X-Rays– Ultrasound– A better and healthier quality of life

• Changes in communication– Telephone,– Radio– Television– Internet,– E-mail

• Changes in culture and free-time – Movies– Radio– Television– Internet