Notes, abstracts, papers, exams and problems of 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

• Rock wool• Glass wool

Divided according to material density to: – very light products (density < 50 kg/m3); – light (density from 50 kg/m3 to 200 kg/m3 ); – heavy (density From 200 kg/m3 to 400 kg/m3 ).

According to compressibility (material affected by 2 kPa load) into: – Soft (compresses more than 30 %); – half rigid (compresses from 6 to 30 %); – Rigid (compresses not more than 6 %).

according to usage for constructions into: – general purpose: • not Withstanding loads (light carcass type) • Withstanding loads (molded concrete Floors) in constructions – outer walls; – flat roofs.

Raw material type is chosen depending on resistance to temperature (basalt wool from 1000ºC, dolomite wool 650ºC, glass 550ºC), fiber... Continue reading "Air law" »

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" »

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

CLASSIFICATION OF MExANIMS

Transmision of motion  

• Lineal transmision- lever, puyey, block and tackle
• Rotary transmision- friction weels, belt drive, gears

Transformation of motion

• rotary lineal- weel, rack and pinion, nut and bolt
• reciprocating- Crank and rod, cranksalf, cam

Motion control

• direction control- ratxed, freeweel
• speed reduction- brake

Energy accumulation

• absorption/dissipation- spring

Connection

• linkage- clutx
• support- plain bearing

LEVERS

class 1: levers can do bot of tose ting, fulcrum is between te force and resistance 

class 2: levers increase te force3 tat we apply, te resistance is between te fulcrum and te force

class 3: levers increase te distance tat te end of te levers moves, te force is between t efulcrum and resistance 

ROTARY TRANSMISION:... Continue reading "Three classification of diesel engines according to speed" »

1.

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