Question 1(a) [3 marks]

Define Renewable Energy and explain its importance.

Answer:

Renewable Energy is energy derived from natural sources that are continuously replenished, such as solar, wind, hydroelectric, biomass, and geothermal energy.

Table: Types of Renewable Energy Sources

Type	Source	Advantage
Solar	Sun's radiation	Clean, abundant
Wind	Air movement	No emissions
Hydro	Water flow	Reliable power
Biomass	Organic matter	Carbon neutral

Importance:

Environmental protection: Reduces pollution and greenhouse gases
Energy security: Reduces dependence on fossil fuels
Economic benefits: Creates jobs and reduces energy costs

Mnemonic: "SEEB" - Solar, Environmental, Economic, Biomass

Question 1(b) [4 marks]

Explain Solar Photovoltaic effect & Principle of photovoltaic conversion.

Answer:

Photovoltaic Effect is the generation of electric current when light strikes a semiconductor material.

Working Principle:

Photon absorption: Light photons hit solar cell surface
Electron excitation: Electrons gain energy and move to conduction band
Charge separation: Built-in electric field separates positive and negative charges
Current generation: Flow of electrons creates DC electricity

Diagram:

    Light Photons
         ↓
    ┌─────────────┐
    │  P-type     │ ← Holes (+)
    │─────────────│ ← Junction
    │  N-type     │ ← Electrons (-)
    └─────────────┘
         ↓
    Electric Current

Mnemonic: "PACE" - Photons, Absorption, Charge, Electricity

Question 1(c) [7 marks]

Describe the types of Electric Vehicle (EV) and different Energy sources for EV.

Answer:

Table: Types of Electric Vehicles

EV Type	Full Form	Power Source	Range
BEV	Battery Electric Vehicle	Battery only	150-400 km
HEV	Hybrid Electric Vehicle	Battery + Engine	600+ km
PHEV	Plug-in Hybrid	Battery + Engine	50-100 km electric
FCEV	Fuel Cell Electric	Hydrogen fuel cell	400-600 km

Energy Sources for EVs:

Battery: Lithium-ion batteries store electrical energy
Fuel Cell: Converts hydrogen to electricity
Ultracapacitor: Quick energy storage and release
Flywheel: Mechanical energy storage
Regenerative Braking: Recovers energy during braking
Hybrid Sources: Combination of multiple energy sources

Diagram: EV Architecture

┌────────────┐    ┌─────────────┐    ┌──────────┐
│   Battery  │────│  Controller │────│  Motor   │
└────────────┘    └─────────────┘    └──────────┘
                         │
                  ┌─────────────┐
                  │ Charging    │
                  │ System      │
                  └─────────────┘

Mnemonic: "BHPF-BUFR" - Battery, Hybrid, Plugin, FuelCell - Battery, Ultracap, Flywheel, Regen

Question 1(c) OR [7 marks]

Discuss different types of Renewable Energy Sources.

Answer:

Table: Renewable Energy Sources Comparison

Source	How it Works	Advantages	Applications
Solar	Converts sunlight to electricity	Clean, abundant	Rooftop systems, farms
Wind	Wind turns turbines	No fuel cost	Wind farms, offshore
Hydroelectric	Water flow generates power	Reliable, long-lasting	Dams, rivers
Biomass	Organic matter combustion	Carbon neutral	Power plants, heating
Geothermal	Earth's heat energy	Constant availability	Heating, electricity

Emerging Trends:

Tidal Wave: Ocean wave energy conversion
Solar Thermal: Concentrated solar power systems
Hydrogen: Clean fuel from renewable sources

Benefits:

Sustainability: Never depletes
Environmental: Minimal pollution
Economic: Reduces energy costs long-term

Mnemonic: "SWHBG-THS" - Solar, Wind, Hydro, Biomass, Geothermal - Tidal, Hydrogen, Solar thermal

Question 2(a) [3 marks]

Define Nanotechnology & List Applications of Nanotechnology.

Answer:

Nanotechnology is the science of manipulating matter at atomic and molecular scale (1-100 nanometers).

Applications:

Electronics: Smaller, faster processors
Medicine: Drug delivery systems
Energy: Solar cells, batteries
Materials: Stronger, lighter composites

Mnemonic: "NEMS" - Nano Electronics, Medicine, Solar

Question 2(b) [4 marks]

Give Full forms of: UAV, IOT, AI, M2M

Answer:

Table: Technology Abbreviations

Abbreviation	Full Form	Application
UAV	Unmanned Aerial Vehicle	Surveillance, delivery
IOT	Internet of Things	Smart homes, cities
AI	Artificial Intelligence	Machine learning, automation
M2M	Machine to Machine	Industrial automation

Mnemonic: "UIAM" - UAV, IOT, AI, M2M

Question 2(c) [7 marks]

Describe the block diagram of a drone and its major components.

Answer:

Block Diagram:

graph TD
    A[Flight Controller] --> B[Motors & Propellers]
    A --> C[GPS Module]
    A --> D[IMU Sensors]
    A --> E[Camera]
    F[Battery] --> A
    G[Remote Controller] --> H[Receiver]
    H --> A
    A --> I[Gimbal]

Major Components:

Flight Controller: Brain of drone, processes sensor data
Motors & Propellers: Provide thrust and control movement
Battery: Powers all electronic components
GPS Module: Provides location and navigation data
IMU Sensors: Measure acceleration, rotation, magnetic field
Camera: Captures images and videos
Gimbal: Stabilizes camera for smooth footage

Working Principle:

Control: Remote sends commands to receiver
Processing: Flight controller interprets commands
Stabilization: IMU sensors maintain balance
Navigation: GPS provides position feedback

Mnemonic: "FMBGIC" - Flight controller, Motors, Battery, GPS, IMU, Camera

Question 2(a) OR [3 marks]

Discuss IOT and its importance.

Answer:

Internet of Things (IOT) connects everyday devices to the internet for data exchange and remote control.

Importance:

Automation: Smart homes and cities
Efficiency: Optimized resource usage
Monitoring: Real-time data collection

Mnemonic: "AEM" - Automation, Efficiency, Monitoring

Question 2(b) OR [4 marks]

Define wearable technology. Name at least three applications of wearable technology.

Answer:

Wearable Technology refers to electronic devices worn on the body to monitor health, fitness, or provide information.

Applications:

Smart Watches: Fitness tracking, notifications
Smart Glasses: Augmented reality, navigation
Health Monitors: Heart rate, blood pressure monitoring

Mnemonic: "WSH" - Watches, Smart glasses, Health monitors

Question 2(c) OR [7 marks]

Explain with the help of Block diagram Smart Street light control and monitoring.

Answer:

Block Diagram:

graph TD
    A[Light Sensor] --> B[Microcontroller]
    C[Motion Sensor] --> B
    D[Communication Module] --> B
    B --> E[LED Street Light]
    B --> F[Dimming Control]
    G[Central Control System] --> D
    H[Power Supply] --> B

Components:

Light Sensor: Detects ambient light levels
Motion Sensor: Detects pedestrian/vehicle movement
Microcontroller: Processes sensor data and controls lighting
Communication Module: Wireless connection to control center
LED Street Light: Energy-efficient lighting
Dimming Control: Adjusts brightness based on need

Working:

Auto ON/OFF: Lights turn on at dusk, off at dawn
Motion Detection: Increases brightness when movement detected
Remote Monitoring: Central system monitors all lights
Energy Saving: Dims lights when no activity detected

Mnemonic: "LMCL" - Light sensor, Motion sensor, Controller, LED

Question 3(a) [3 marks]

Compare Organic and Inorganic electronics.

Answer:

Table: Organic vs Inorganic Electronics

Parameter	Organic Electronics	Inorganic Electronics
Material	Carbon-based compounds	Silicon, metals
Cost	Lower manufacturing cost	Higher cost
Flexibility	Flexible, bendable	Rigid structure
Processing	Low temperature	High temperature

Mnemonic: "MCFP" - Material, Cost, Flexibility, Processing

Question 3(b) [4 marks]

Write a short note on OPVD.

Answer:

OPVD (Organic Photovoltaic Devices) are solar cells made from organic semiconducting materials.

Characteristics:

Flexible: Can be made on flexible substrates
Low-cost: Cheaper manufacturing process
Lightweight: Suitable for portable applications
Semi-transparent: Can be integrated into windows

Applications:

Building Integration: Solar windows
Portable Devices: Flexible solar chargers
Wearable Electronics: Solar-powered gadgets

Mnemonic: "FLLW" - Flexible, Low-cost, Lightweight, Windows

Question 3(c) [7 marks]

Explain Biometric systems and their basic block diagram.

Answer:

Biometric System identifies individuals based on unique biological characteristics.

Block Diagram:

graph LR
    A[Biometric Sensor] --> B[Signal Processing]
    B --> C[Feature Extraction]
    C --> D[Template Matching]
    D --> E[Decision Module]
    F[Database] --> D
    E --> G[Accept/Reject]

Components:

Sensor Module: Captures biometric data (fingerprint, iris, face)
Signal Processing: Enhances and cleans captured signal
Feature Extraction: Identifies unique characteristics
Database Module: Stores biometric templates
Matching Module: Compares captured data with stored templates
Decision Module: Makes final accept/reject decision

Types of Biometrics:

Fingerprint: Ridge patterns on fingers
Iris: Eye iris patterns
Face Recognition: Facial features
Voice: Voice patterns and characteristics

Applications:

Security: Access control systems
Banking: ATM authentication
Mobile: Phone unlocking
Border Control: Immigration systems

Mnemonic: "SFEMD" - Sensor, Feature extraction, Matching, Database, Decision

Question 3(a) OR [3 marks]

List the advantages and applications of organic electronics.

Answer:

Advantages:

Flexible: Bendable electronic devices
Low-cost: Cheaper manufacturing
Large-area: Can cover large surfaces

Applications:

OLED Displays: Flexible screens
Solar Cells: Lightweight panels
RFID Tags: Flexible identification

Mnemonic: "FLL-OSR" - Flexible, Low-cost, Large-area - OLED, Solar, RFID

Question 3(b) OR [4 marks]

Write a short note on OLED.

Answer:

OLED (Organic Light Emitting Diode) is a display technology using organic compounds that emit light when electric current is applied.

Advantages:

Self-illuminating: No backlight needed
High contrast: True black colors
Flexible: Can be bent and curved
Energy efficient: Lower power consumption

Applications:

Smartphones: OLED screens
TVs: Ultra-thin displays
Wearables: Smartwatch displays

Mnemonic: "SHFE" - Self-illuminating, High contrast, Flexible, Efficient

Question 3(c) OR [7 marks]

Explain AR/VR core technology and discuss its applications.

Answer:

AR (Augmented Reality) overlays digital information on real world, while VR (Virtual Reality) creates completely immersive digital environment.

Core Technologies:

Display Systems: Head-mounted displays, screens
Tracking Systems: Motion sensors, cameras
Processing Units: GPU, specialized chips
Input Methods: Controllers, gesture recognition

AR Applications:

Gaming: Pokemon Go, mobile AR games
Education: Interactive learning experiences
Navigation: GPS overlays on real roads
Shopping: Virtual try-on experiences

VR Applications:

Entertainment: Immersive gaming, movies
Training: Flight simulators, medical training
Architecture: Virtual building walkthroughs
Therapy: Treatment of phobias, PTSD

Table: AR vs VR Comparison

Aspect	AR	VR
Reality	Mixed with real world	Completely virtual
Equipment	Smartphone, AR glasses	VR headset, controllers
Immersion	Partial	Complete
Mobility	Mobile friendly	Stationary setup

Mnemonic: "DTPI-GENT" - Display, Tracking, Processing, Input - Gaming, Education, Navigation, Training

Question 4(a) [3 marks]

Draw Block Diagram of a Home Solar rooftop system.

Answer:

Block Diagram:

┌─────────────┐    ┌─────────────┐    ┌─────────────┐
│Solar Panels │────│   Inverter  │────│AC Load Panel│
└─────────────┘    └─────────────┘    └─────────────┘
                          │                   │
                   ┌─────────────┐    ┌─────────────┐
                   │   Battery   │    │Utility Grid │
                   │   Storage   │    │ Connection  │
                   └─────────────┘    └─────────────┘

Components:

Solar Panels: Convert sunlight to DC electricity
Inverter: Converts DC to AC power
Battery Storage: Stores excess energy

Mnemonic: "SIB" - Solar panels, Inverter, Battery

Question 4(b) [4 marks]

Explain working principle of OFET.

Answer:

OFET (Organic Field Effect Transistor) uses organic semiconductors to control current flow.

Working Principle:

Gate Voltage: Applied voltage creates electric field
Channel Formation: Electric field modulates conductivity
Current Control: Source-drain current controlled by gate
Switching: ON/OFF states for digital applications

Structure:

Source/Drain: Current injection points
Gate: Control electrode
Organic Layer: Active semiconductor material

Mnemonic: "GCCS" - Gate voltage, Channel, Current, Switching

Question 4(c) [7 marks]

List various Machine learning tools. Discuss any two in brief.

Answer:

Machine Learning Tools:

TensorFlow: Google's ML framework
PyTorch: Facebook's deep learning library
Scikit-learn: Python ML library
Keras: High-level neural network API
Machine Learning for Kids: Educational platform
Scratch: Visual programming for ML

TensorFlow:

Purpose: Deep learning and neural networks
Features: Large-scale ML, production deployment
Applications: Image recognition, NLP, recommendation systems
Advantages: Scalable, extensive documentation

Scikit-learn:

Purpose: General machine learning algorithms
Features: Classification, regression, clustering
Applications: Data analysis, predictive modeling
Advantages: Easy to use, well-documented

Table: ML Tools Comparison

Tool	Type	Best For	Difficulty
TensorFlow	Deep Learning	Complex models	Advanced
Scikit-learn	General ML	Beginners	Easy

Mnemonic: "TPSKMS-TF.SL" - TensorFlow, PyTorch, Scikit, Keras, ML4Kids, Scratch - TensorFlow, Scikit-learn

Question 4(a) OR [3 marks]

Briefly explain Emerging Trends in Renewable Energy.

Answer:

Emerging Trends:

Floating Solar: Solar panels on water bodies
Perovskite Cells: Next-generation solar technology
Green Hydrogen: Clean fuel from renewable sources

Benefits:

Higher efficiency: Better energy conversion
Cost reduction: Cheaper renewable energy

Mnemonic: "FPG" - Floating solar, Perovskite, Green hydrogen

Question 4(b) OR [4 marks]

Give Full forms of: AR, OLED, OPVD, OFET

Answer:

Table: Technology Full Forms

Abbreviation	Full Form	Technology Area
AR	Augmented Reality	Mixed reality
OLED	Organic Light Emitting Diode	Display technology
OPVD	Organic Photovoltaic Device	Solar cells
OFET	Organic Field Effect Transistor	Electronics

Mnemonic: "AOOO" - AR, OLED, OPVD, OFET

Question 4(c) OR [7 marks]

Explain Block diagram of Raspberry Pi.

Answer:

Block Diagram:

graph TD
    A[ARM Processor] --> B[RAM Memory]
    A --> C[GPIO Pins]
    A --> D[USB Ports]
    A --> E[HDMI Output]
    A --> F[Ethernet Port]
    G[MicroSD Card] --> A
    H[Power Supply] --> A
    A --> I[Audio/Video]

Components:

ARM Processor: Central processing unit (Quad-core)
RAM Memory: System memory (1GB-8GB)
GPIO Pins: 40 pins for interfacing sensors/devices
USB Ports: Connect peripherals
HDMI Output: Video display connection
Ethernet Port: Network connectivity
MicroSD Card: Storage for OS and data
Power Supply: 5V micro-USB or USB-C

Features:

Operating System: Raspberry Pi OS (Linux-based)
Programming: Python, C++, Scratch support
Connectivity: Wi-Fi, Bluetooth built-in
Expandability: Camera, display connectors

Applications:

IoT Projects: Home automation
Education: Learning programming
Robotics: Robot control systems
Media Center: Home entertainment

Mnemonic: "ARGC-EPMS" - ARM, RAM, GPIO, Connectivity - Ethernet, Power, MicroSD, Storage

Question 5(a) [3 marks]

Interface LED with Raspberry Pi.

Answer:

Circuit Connection:

Raspberry Pi          LED Circuit
GPIO Pin 18 ────── 220Ω ────── LED ────── GND
                   Resistor    Anode     Cathode

Python Code:

import RPi.GPIO as GPIO
import time

GPIO.setmode(GPIO.BCM)
GPIO.setup(18, GPIO.OUT)

while True:
    GPIO.output(18, GPIO.HIGH)  # LED ON
    time.sleep(1)
    GPIO.output(18, GPIO.LOW)   # LED OFF
    time.sleep(1)

Mnemonic: "GPIO-RC" - GPIO pin, Resistor, Code

Question 5(b) [4 marks]

Explain Pandas python library For Machine Learning.

Answer:

Pandas is a Python library for data manipulation and analysis, essential for ML data preprocessing.

Key Features:

DataFrame: Tabular data structure
Data Cleaning: Handle missing values, duplicates
Data Import: Read CSV, Excel, JSON files
Data Analysis: Statistical operations, grouping

ML Applications:

Data Preprocessing: Clean and prepare datasets
Feature Engineering: Create new features from data
Data Exploration: Understand data patterns
Data Transformation: Normalize, scale data

Common Functions:

import pandas as pd
df = pd.read_csv('data.csv')    # Load data
df.info()                       # Data info
df.describe()                   # Statistics

Mnemonic: "DCIF" - DataFrame, Cleaning, Import, Functions

Question 5(c) [7 marks]

Explain types of machine learning techniques: supervised, unsupervised and reinforcement learning.

Answer:

Table: Machine Learning Types

Type	Data Required	Goal	Examples
Supervised	Labeled data	Predict outcomes	Classification, Regression
Unsupervised	Unlabeled data	Find patterns	Clustering, Dimensionality reduction
Reinforcement	Reward signals	Learn optimal actions	Game playing, Robotics

Supervised Learning:

Definition: Learns from input-output pairs
Process: Training with known answers
Applications: Email spam detection, image recognition
Algorithms: Linear regression, decision trees, neural networks

Unsupervised Learning:

Definition: Finds hidden patterns in data
Process: No target variable provided
Applications: Customer segmentation, anomaly detection
Algorithms: K-means clustering, PCA, hierarchical clustering

Reinforcement Learning:

Definition: Learns through trial and error
Process: Agent interacts with environment
Applications: Game AI, autonomous vehicles, robotics
Components: Agent, environment, rewards, actions

Diagram: ML Learning Process

graph LR
    A[Data] --> B{Learning Type}
    B --> C[Supervised]
    B --> D[Unsupervised]
    B --> E[Reinforcement]
    C --> F[Prediction Model]
    D --> G[Pattern Discovery]
    E --> H[Decision Policy]

Mnemonic: "SUR-PLR-CPD" - Supervised, Unsupervised, Reinforcement - Prediction, Learning, Rewards - Classification, Patterns, Decisions

Question 5(a) OR [3 marks]

Explain NumPy python library For Machine Learning.

Answer:

NumPy is fundamental library for numerical computing in Python, essential for ML operations.

Key Features:

Arrays: Multi-dimensional array objects
Mathematical Functions: Linear algebra operations
Broadcasting: Operations on different sized arrays

ML Applications:

Data Storage: Efficient numerical data storage
Matrix Operations: Neural network computations
Mathematical Computations: Statistical operations

Mnemonic: "AMB" - Arrays, Mathematical functions, Broadcasting

Question 5(b) OR [4 marks]

Write Installation steps of Raspberry Pi OS on SD card using Raspberry Pi Imager.

Answer:

Installation Steps:

Download: Install Raspberry Pi Imager from official website
Insert SD Card: Connect SD card (16GB+) to computer
Select OS: Choose Raspberry Pi OS from list
Select Storage: Choose SD card as target
Write: Click "Write" to flash OS to SD card
Eject: Safely remove SD card after completion

Pre-configuration Options:

Enable SSH: For remote access
Set Username/Password: Security credentials
Configure Wi-Fi: Network settings

Mnemonic: "DISWS-ESP" - Download, Insert, Select OS, Write, Storage - Enable SSH, Set credentials, Pre-configure

Question 5(c) OR [7 marks]

Interface Temperature and humidity sensors with Raspberry Pi and write Python Program for it.

Answer:

Circuit Connection:

DHT22 Sensor          Raspberry Pi
VCC  ────────────────  3.3V (Pin 1)
DATA ────────────────  GPIO 4 (Pin 7)
GND  ────────────────  GND (Pin 6)

Python Program:

import Adafruit_DHT
import time

# Sensor type and GPIO pin
sensor = Adafruit_DHT.DHT22
pin = 4

while True:
    try:
        # Read sensor data
        humidity, temperature = Adafruit_DHT.read_retry(sensor, pin)
        
        if humidity is not None and temperature is not None:
            print(f'Temperature: {temperature:.1f}°C')
            print(f'Humidity: {humidity:.1f}%')
        else:
            print('Failed to read sensor data')
            
        time.sleep(2)  # Wait 2 seconds
        
    except KeyboardInterrupt:
        print("\nProgram stopped")
        break

Required Library:

pip install Adafruit_DHT

Components Used:

DHT22: Temperature and humidity sensor
Raspberry Pi: Processing unit
Python: Programming language
Adafruit Library: Sensor interface library

Features:

Real-time Reading: Continuous monitoring
Error Handling: Handles sensor read failures
Data Display: Shows temperature and humidity values
User Control: Keyboard interrupt to stop program

Applications:

Weather Station: Local weather monitoring
Home Automation: Climate control systems
Agriculture: Greenhouse monitoring
Industrial: Environmental monitoring

Mnemonic: "DHT-RPL" - DHT sensor, Raspberry Pi, Python, Library