Fundamentals of Technology and Basic Electronics
1. What Is Technology?
Technology is the application of knowledge and skills to solve problems and satisfy human needs.
Technology helps people create objects and systems that make life easier, such as machines, tools, transport, and communication devices.
Technology uses:
- Scientific and technical knowledge
- Technical skills
- Technical drawings
- Computers
- Economic factors (costs and prices)
2. Stages of Technological Projects
A technological project follows these stages:
- Needs – Identify a problem or need.
- Ideas – Propose different solutions and choose the best one.
- Develop the ideas – Make technical drawings, prepare a budget, and create a construction plan.
- Construction – Build the solution.
- Verification – Test the product and correct errors.
- Marketing – Sell and promote the product.
3. Materials Used in Technology
Common materials and typical uses:
- Wood – Comes from trees. Used for furniture, paper, and construction.
- Plastics – Made from oil, gas, or plants. Used for bottles, toys, and containers.
- Metals and alloys – Extracted from rocks. Used for tools, machines, and screws.
- Ferrous metals contain iron.
- Non-ferrous metals do not contain iron.
- Textiles – Made from plants or animals. Used for clothes and carpets.
- Stone – Used in buildings and decoration.
4. Tools Used in Technology
Types of tools commonly used:
- Drawing tools – Pencil, ruler, compass, and set square.
- Physical tools – Hammer, saw, drill, and screwdriver.
- Digital tools – Computers, word processors, spreadsheets, presentation programs, 3D design software, and simulators.
5. Businesses
A business is an organization that produces goods and services to make a profit.
A business has three main parts:
- Management – Plans and makes decisions.
- Production – Makes the product.
- Logistics – Delivers and sells the product to customers.
6. How Technology Influences Society
Technology changes the way people:
- Work
- Communicate
- Travel
- Study
New technologies help society grow and develop.
7. Environmental Impact of Technology
Technology can help or harm the environment.
Sustainable development means meeting today’s needs without damaging the future.
Important actions:
- Recycling
- Using clean energy
- Reducing waste
1. Electrical Circuits
An electrical circuit is a set of connected components that allows electric current to flow.
Electric current is the continuous flow of electric charges (electrons).
A generator (battery or cell) provides energy and creates a potential difference (voltage).
Loads transform electrical energy into:
- Light (bulb, LED)
- Movement (motor)
- Heat (resistor)
- Sound (bell, speaker)
Switching devices control the flow of electricity.
Safety components protect the circuit (fuse).
2. Electrical Quantities
Voltage (V)
Voltage is the energy available to move electrons in a circuit.
It is measured in volts (V).
Electric Current (I)
Electric current is the amount of charge that flows in one second.
It is measured in amperes (A).
Formula:
I = Q / t
Resistance (R)
Resistance is how much a component opposes the flow of current.
It is measured in ohms (Ω).
3. Ohm’s Law
Ohm’s law relates voltage, current, and resistance:
- I = V / R
- V = I · R
- R = V / I
If voltage increases → current increases.
If resistance increases → current decreases.
4. Energy and Electrical Power
Electrical Energy (E)
Energy used by a device over time.
Formula:
E = V · I · t
Measured in joules (J) or kilowatt-hours (kWh).
Electrical Power (P)
Power is how fast energy is used.
Formula:
P = V · I
Measured in watts (W).
6. Series and Parallel Circuits
Series Circuit
- The same current flows through all components.
- Voltage is shared between components.
- If one component fails → all stop working.
Parallel Circuit
- The same voltage is across all components.
- Current is divided between branches.
- If one component fails → others still work.
7. Combination Circuits
These circuits have series and parallel parts.
They are analyzed using:
- Ohm’s Law
- Kirchhoff’s laws:
- Total current entering a junction = total current leaving.
- Total voltage in a closed loop = 0.
8. Electronics
Electronics studies circuits that control and modify current using semiconductor components.
9. Electronic Components
Resistors
- Limit the flow of current.
- Their value is shown using colour bands.
Variable resistors (potentiometers)
Resistance can be adjusted manually.
Thermistors
Resistance changes with temperature:
- PTC → resistance increases when temperature increases.
- NTC → resistance decreases when temperature increases.
LDR (Light Dependent Resistor)
Resistance decreases when light increases.
10. Capacitors
A capacitor stores electrical energy and releases it slowly.
Capacitance is measured in farads (F).
11. Diodes
A diode allows current to flow in only one direction.
An LED is a diode that produces light.
12. Transistors
A transistor is an electronic switch controlled by a small current.
It has three parts:
- Base (B)
- Collector (C)
- Emitter (E)
States:
- Cutoff → OFF
- Active → working normally
- Saturation → fully ON
Used to amplify signals or control devices.
13. Relays
A relay is an automatic switch controlled by an electromagnet.
It allows a low-voltage circuit to control a high-voltage device.