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

Understanding Electrical Safety and Protection

The physiological effects and after-effects of electric current are determined by several critical factors:

• Type of current
• Current magnitude
• Frequency
• Duration of current passing through the body
• Resistance of the human body
• The insulation properties of the skin

Conductor Identification: Notation and Colors

Proper identification of conductors is crucial for electrical safety. Here are the standard notations and colors for insulated conductors:

• Working Conductor: Wire of the current system for power supply and energy transmission. Colors: Black, Brown, and Grey.
• Neutral Conductor: Wire connected to the source node, which contributes to energy transmission. Color: Light Blue.
• Protective Conductor: Wire required

Computer Fundamentals

Basic Computer Scheme

Input, Process, Output.

Binary Code

Information in a PC is processed using binary code.

RAM (Random Access Memory)

A type of data storage generally located on the motherboard. It is volatile; all information is lost when the computer turns off.

ROM (Read-Only Memory)

A non-volatile memory used in computers and other electronic devices.

CPU (Central Processing Unit)

The brain of the computer where most calculations take place. The CPU is the most important part of a computer system.

Motherboard

The physical arrangement in a computer that contains all the computer's components.

Analog vs. Digital Technology

In analog technology, information is translated into electric pulses of varying amplitude. In digital technology,... Continue reading "Computer Fundamentals and Internet Connections" »

Home Automation and Telecommunication

Home Automation

Home Automation refers to the use of computer and information technology to control a home. This includes various aspects such as:

• HVAC (Heating, Ventilation, and Air Conditioning): Controls the temperature and air quality in your home.
• Lighting: Allows you to control lights remotely and automate lighting schedules.
• Intercom: Enables communication within the home or with visitors at the door.
• Smart Window: Windows that can be automatically tinted or adjusted for optimal energy efficiency.
• Video Door Phone System: Allows you to see and communicate with visitors at your door remotely.
• Socket: Smart sockets that can be controlled remotely and monitor energy usage.
• TV Set: Integration with smart TVs

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,