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

parallel circuits

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" »

English Grammar Essentials for Technical Communication

Past Simple Tense

Regular Verbs

• Affirmative (+): Infinitive + -ed (e.g., walked)
• Negative (-): Did not (didn't) + Infinitive (e.g., didn't walk)
• Interrogative (?): Did + Subject + Infinitive? (e.g., Did you walk?)

Irregular Verbs

• Affirmative (+): Irregular Verb (Past Form) (e.g., go/went)
• Negative (-): Subject + Did not (didn't) + Infinitive (e.g., He didn't go)
• Interrogative (?): Did + Subject + Infinitive? (e.g., Did she go?)

Future Simple Tense

• Affirmative (+): Will + Infinitive (e.g., will work)
• Negative (-): Will not (won't) + Infinitive (e.g., won't work)
• Interrogative (?): Will + Subject + Infinitive? (e.g., Will they work?)

Future with "Be Going To"

• Affirmative (+): Am/Is/Are + Going To + Infinitive

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" »

Understanding Computer Networks

What is a Computer Network?

A computer network is a collection of interconnected computers and devices, linked either physically or wirelessly, for the primary purpose of sharing information and resources.

Types of Computer Networks

Computer networks are primarily classified by their size and geographical reach into two main types:

• Local Area Network (LAN): These networks cover a limited geographical area, typically within a single building or a small campus. They are the most common type, found in offices, homes, and schools. Example: The network connecting computers within a classroom or an office building.
• Wide Area Network (WAN): These are powerful networks that connect computers located in different cities, countries,

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