Notes, summaries, assignments, exams, and problems for Technology

Mechanisms

Mechanisms are devices that transform movement. They can change the speed, direction, force, or type of movement.

Belts and Pulleys

A belt passes around two pulley wheels. If the driver wheel moves, it moves the belt, and the belt moves the driven wheel.

A pulley is a wheel that turns when a rope, belt, or chain passes through it.

Levers

The lever is a basic mechanism. It's typically made of a bar of wood or metal that pivots around a fixed point called a fulcrum.

• First-type lever Examples: Scissors, pliers, bottle opener, seesaw.
• Second-type lever Examples: Wheelbarrow, paint chippers, nutcrackers.
• Third-type lever Examples: Catapult, baseball bat, human arm.

Effort x Effort arm = Load x Load arm

Questions about levers and pulleys

1. What does

Mechanisms

A mechanism is a group of elements that transmit and transform forces and movements from a motive (or driver) element to a receptor (or driven) element. Mechanisms allow us to perform operations more easily and with less effort.

Classification of Mechanisms

• Movement Transmission Mechanisms
  • Linear Transmission (e.g., pulleys, levers)
  • Circular Transmission (e.g., friction wheels, pulleys and belts, gears, chain drives)
• Movement Transformation Mechanisms (e.g., rack and pinion, handle-winch, crank-connecting rod, cam and eccentric)

Lever

A lever is a rigid bar that pivots around a fixed point called a fulcrum. It is used to amplify force, allowing a larger force to be overcome with a smaller effort. However, to achieve this force multiplication,... Continue reading "Mechanisms: Levers, Pulleys, Gears, and More" »

Protecting Your Digital Identity

Person’s digital identity: Is all information that you can find about a person on the internet, written by itself or other people. It is important because if you are looking for a job, everyone can see it and you have to be aware.

Best Way to Back Up Your Information

Best way to do a backup of your information: First and foremost, you need to back up your personal files. You can always reinstall your operating system and redownload your programs if your hard drive fails, but your own personal data is irreplaceable. Any personal documents, photos, home videos, and any other data on your computer should be backed up regularly. Those can never be replaced. Your operating system, programs, and other settings can... Continue reading "Protecting Your Digital Identity and Backing Up Your Data" »

Acording to Iron Content:

Ferrous: iron or alloys containing iron. Non-ferrous: pure metals not iron or metal.

Acording to Density:

Ultralight: density < 2g/cm3. Light: density 2-5g/cm3. Heavy: density > g/cm3.

Process of Obtaining Metals:

1. Obtaining minerals from mines and pits
2. Separation of mineral into ore and gangue
3. Obtaining pure metal from mineral
4. Final treatment

Mining:

Industrial activity extracting elements, compounds, and minerals of economic interest from earth. Two types of mines: open air and underground.

Siderurgy:

Industry dedicated to obtaining iron. Raw materials: iron ores, limestone, and coke coal. Process: raw materials put into blast furnace, hot air introduced, chemical reaction occurs, waste materials (slag) stay at top, molten... Continue reading "Metals and Alloys: Types, Processes, and Applications" »

Arduino Libraries: Extending Functionality

The Arduino environment, much like most programming platforms, can be significantly extended through the use of libraries. These libraries provide additional functionality, making it easier to implement complex features and interact with various hardware components in your sketches.

Arduino Servo Library Capabilities

The Servo library is essential for controlling servo motors. It supports up to 12 motors on most Arduino boards and an impressive 48 motors on the Arduino Mega. It's important to note that on boards other than the Mega, using the Servo library disables analogWrite() (PWM) functionality on pins 9 and 10, regardless of whether a servo is connected to those specific pins. On the Arduino Mega,... Continue reading "Arduino Library Essentials: Servo, Bluetooth, SoftwareSerial" »

Metal Matrix Composites (MMCs)

Metal matrix composites (MMCs) can be classified based on the type of metal used as the matrix. The classification of metals in MMCs includes:

1. Pure Metals: These are metals composed of a single element, such as aluminum (Al), copper (Cu), titanium (Ti), or magnesium (Mg). Pure metals can serve as matrices in MMCs, providing specific properties and characteristics.
2. Intermetallic Compounds: Intermetallics are compounds formed by the combination of two or more metallic elements. They possess a distinct crystal structure and can exhibit unique properties. Intermetallic compounds, such as titanium aluminides (Ti-Al) or nickel aluminides (Ni-Al), can be used as matrices in MMCs.
3. Alloys: Alloys are metallic materials composed

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Types of Knives

Chef's Knife (Cebollero)

• All purpose knife for peeling, trimming, chopping, slicing, and dicing
• Triangular blade, rock chop

Utility Knife or Salad Knife

• All purpose, smaller than the chef's knife
• Used specially for peeling and slicing fruit and vegetables

Santoku Knife or Japanese Cook's Knife

• Sheep's foot tip
• Top chop

Paring Knife

• Used for paring or peeling fruits and vegetables

Tournée Knife

• Sometimes considered as a kind of paring knife
• Used for turning vegetables

Slicer Knife

• Long slender and flexible blade
• Used for carving or slicing cooked meats

Bread Knife or Serrated Slicer

Used to cut bread, cakes, and similar food

Boning Knife

• Thin and pointed blade
• Used for boning raw meats, poultry, and fish
• Used for trimming fat from meats

Filleting Knife

• Pointed

Essential Kitchen Cutting Tools

Vegetable Peeler

A short tool with a slotted, swiveling blade used for peeling vegetables and fruits. There are two types: Swiss peeler and standard peeler.

Mandoline

A manual slicer with adjustable blades for creating various cuts, such as julienne, batonnet, and waffle slices.

Sharpening Steel

Used for honing and maintaining knife edges, keeping them sharp with regular use. Not intended for sharpening dull knives.

Sharpening Stone

Also known as a whetstone, used to sharpen dull knives and refine their edges.

Cutting Board

Made of wood, plastic, or composite material, used as a stable surface for cutting, chopping, and other food preparation tasks.

Scissors

Versatile kitchen tool for various tasks, such as snipping herbs,... Continue reading "Essential Kitchen Cutting Tools and Techniques" »