Notes, summaries, assignments, exams, and exercises for Technology for Secondary education

Q1. Synchronous

1. Asynchronous
2. Isochronous
3. None of the above

Q2. Full Duplex

1. Half Duplex
2. Simplex
3. All of the above

Q3. Modulation

1. De-modulation
2. Multiplexing
3. De-multiplexing

Q4. TDM

1. WDM
2. CDM
3. All of the above

Q5. FDM

1. TDM
2. WDM
3. CDM

Q6. Electrical

1. Light
2. Electromagnetic
3. All of the above

Q7. Less Susceptible

1. More Susceptible
2. Not Susceptible
3. None of the above

Q8. Fiber Optic

1. Twisted Pair Cable
2. Coaxial Cable
3. Both B & C

Q9. Reflected

1. Refracted
2. Travelling along the boundary
3. None of the above

Q10. Digital

1. Analogue
2. Both A & B
3. None of the above

Q11. Phase and in Amplitude

1. Phase and Frequency
2. Amplitude and Frequency
3. All of the above

Q12. Increased Unused Slots

1. Decrease the Unused Slots (Maybe)
2. Eliminating Unused Slots
3. Do Not Deal with Unused Slots

Q13. Mathematical Formula

1. Analogue Signal
2. Digital Signal
3. Any

Understanding Electricity and Electronics

Electricity

Matter is formed by atoms consisting of negatively charged particles (electrons) and positively charged particles (protons). Between these particles, there are forces of attraction or repulsion that generate a type of energy called electricity.

In a balanced atom, the number of protons is equal to the number of electrons. The forces of attraction and repulsion between these particles are balanced. When this balance is disturbed, the electrical forces become unbalanced and the electrons are driven by their electrical energy to other atoms in search of new balances.

We call this transfer of charges electrical current, and it is produced in conducting materials.

Conducting materials transmit electrical...

An annotation is the measure of a property of an object which must be specified in a technical drawing. Narrowing, also known as height or size, must meet a set of rules for readability and therefore facilitate the construction of a piece.

• Cota Lines: These are fine lines that indicate the exact size of each part of the piece. Are interrupted at its center for placement of dimensions or measures of that party. Thickness must be thin and an arrowhead. These indicate the beginning and end of each line. Dimension lines to be available so they are outside the contour of the piece.

• Cota Construction Lines: These are solid lines, which starting from the limit order to narrow space. Are drawn perpendicular to the dimension exceeds 1 or 2 mm. If the

Graphic Design Fundamentals

Graphic design involves creating drawings to represent objects, products, or to transmit ideas, events, and messages, while considering function, cost, size, shape, quality, and environmental impact.

Understanding Drawing Scales

Scale is the relationship between the size of a drawing and the actual size of the object:

• 1:2 (Scaling down): The drawing is smaller than the real object; used for large items like houses, cars, or planes.
• 1:1 (Full scale): The drawing matches the real-life measurements; used for objects like pencil cases.
• 2:1 (Scaling up): The drawing is larger than the real object; used for small items like bacteria or viruses.

Isometric Perspective

Isometric means equal measure. It utilizes 120° and 30° angles...

Malware

Malicious software, is a type of software that has been particularly designed to gain access to or damage a computer, mostly without the knowledge of the owner. There are a lot of types of malware, including computer worm, computer viruses, Trojan horse, adware and spyware.

Computer Crime

Defined as a crime in which a computer is the object of the crime (hacking, phishing, spamming) or is used as a tool to commit an offense (child pornography, hate crimes). Cybercriminals may use computer technology to access personal information, business secrets or use the internet for malicious purposes.

Trojan Horse

A type of malware that is often disguised as legitimate software. Trojans can be employed by cyber-thieves and hackers that offer useful...

VLAN Configuration and Troubleshooting

Common VLAN Issues and Solutions

VLAN Mismatch

Problem: RTA uses the same sub-interface for VLAN 20 and VLAN 30.

Solution: Ensure each VLAN is assigned a unique sub-interface.

Adding VLANs

Problem: How to add VLAN 10?

Solution: Switch1(config)# vlan 10

Incorrect VLAN Tagging

Problem: The dot1Q encapsulation command contains the wrong VLAN for PC1 and PC2.

Solution: Verify and correct the VLAN tag in the dot1Q command.

Trunk Mode Verification

Problem: Network admin verification: Gi1/1 is configured as trunk mode, but Gi1/1 is in the default VLAN.

Solution: Ensure Gi1/1 is correctly configured for trunk mode and assigned to the appropriate VLANs.

Inter-VLAN Communication

Problem: Communication between VLANs is not working....

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,...

Force

Force is an action capable of producing or modifying the state of motion or deformation. It can be observed through the effects produced by contact or distance between two bodies. Forces are represented by arrows indicating direction and sense. They are measured using a dynamometer, with the unit being Newton.

Mechanical Properties

Mechanical properties determine the behavior of materials when subjected to forces.

Resistance

The ability of a material to resist forces without distorting or breaking.

• Tenacity and Fragility: Tenacity is the property of a material to withstand forces and shocks without breaking, while fragility is the opposite.
• Elasticity: The property of a material to recover its original shape after being deformed by a force.
• Plasticity:

Autonomous Robot Behaviors and Sensor Mechanisms

Robot Light-Seeking Mechanism (Initial Description)

When the robot is connected, one motor begins to rotate forward and the other remains stationary. Therefore, the robot turns on itself (1). When the front light sensor detects a light source or a clear zone (such as a flashlight, a white wall, or a window), the motor activates, causing the robot to move toward the light (2). If the robot detects no light, the sensor monitors the motor stops, and the robot starts to spin again until it detects light.

Robot Crawler (Line Follower)

When the robot is placed on a white surface, the high-brightness Light Emitting Diodes (LEDs) reflect light, which is detected by the Light Dependent Resistors (LDRs). The...

DC Machine Problem: Induced EMF and Torque Calculation

This section details the calculation of induced electromotive force (EMF) and internal mechanical torque for a specific DC machine, along with its key parameters.

DC Machine Parameters and Specifications

• Type: 4-pole shunt excitation DC machine
• Power: 11 KW
• Voltage: 440 V
• Speed: 750 rpm
• Winding: 31 slots, 30 conductors per slot (Total conductors, N_c = 31 × 30 = 930)
• Diameter (D): 24 cm (0.24 m)
• Stacking Factor: 71% (0.71)
• Air Gap: 3.1 mm
• Maximum Vacuum Flux Density (B_max): 0.705 T
• Losses: 325 W (at full load)

Key Formulas and Calculations

• Number of Conductors (N_c): N_c = Number of slots × Conductors per slot = 31 × 30 = 930
• Winding Type: The original text mentions "2 winding hilly roads then a = 1".