(SEM VII) THEORY EXAMINATION 2023-24 MOBILE APPLICATION DEVELOPMENT FOR IOT

MOBILE APPLICATION DEVELOPMENT FOR IoT (KOT712)

B.Tech SEM VII – Complete Solved Question Paper (2023–24)

SECTION A

Attempt all questions in brief (2 × 10 = 20 Marks)

(a) Enlist the different display devices used in IoT

Common display devices used in IoT are:                          16×2 LCD

OLED display                                                                       TFT display

LED indicators                                                                      Nokia 5110 LCD

(b) Define LDR and its application in IoT

An LDR (Light Dependent Resistor) is a sensor whose resistance changes with light intensity.
Application: Automatic street lights, light monitoring systems, and smart home lighting.

(c) Discuss the working principle of MQ2 sensor

The MQ2 sensor detects gases like LPG, smoke, and methane. Its resistance changes when gas concentration increases, producing an analog signal that can be processed by a microcontroller.

(d) Define Blynk app and its application

Blynk is a mobile application platform used to control and monitor IoT devices remotely using smartphones.
Application: Home automation, sensor monitoring, and device control.

(e) What is cloud IoT?

Cloud IoT refers to using cloud platforms to store, process, analyze, and visualize data generated by IoT devices over the internet.

(f) Define optimization in IoT product development

Optimization is the process of improving performance, power efficiency, cost, and reliability of IoT products by selecting suitable hardware, software, and communication methods.

(g) Enlist the merits of master and slave module

Merits include:                                                                 Efficient communication control

Reduced data collision                                                    Easy synchronization

Simplified network structure

(h) Discuss the application of ThingSpeak

ThingSpeak is used for data collection, storage, visualization, and real-time analytics of IoT sensor data using cloud services.

(i) What do you mean by IoT warehouse?

An IoT warehouse is a smart storage facility that uses sensors and IoT devices to monitor temperature, humidity, gas, inventory, and security conditions.

(j) Discuss the features of IoT warehouse monitoring system

Features include real-time monitoring, automated alerts, cloud data storage, remote access, improved safety, and efficient inventory management.

SECTION B

Attempt any THREE (10 × 3 = 30 Marks)

(a) Explain the gas level detection in IoT system

Gas level detection in an IoT system uses gas sensors such as MQ2 or MQ135 to detect harmful gases. The sensor outputs an analog signal proportional to gas concentration. This data is processed by a microcontroller and sent to cloud platforms for monitoring. Alerts are generated if gas levels exceed safe limits, ensuring safety in homes and industries.

(b) Write a program to display temperature values on 16×2 LCD display in Arduino. Also draw the pinout of 16×2 LCD display

Arduino Program (Example):

#include <LiquidCrystal.h> LiquidCrystal lcd(12,11,5,4,3,2); void setup() {  lcd.begin(16,2); } void loop() {  int temp = 25;  lcd.setCursor(0,0);  lcd.print("Temp: ");  lcd.print(temp);  lcd.print(" C");  delay(1000); }

Pinout of 16×2 LCD:                                  VSS – Ground

VDD – +5V                                                   V0 – Contrast

RS – Register Select                                      RW – Read/Write

EN – Enable                                                  D0–D7 – Data pins

(👉 In exam, draw neat labeled diagram)

(c) Explain the different types of customizations and optimization routine followed in IoT product hardware development

Customization includes selecting suitable sensors, microcontrollers, power modules, and communication interfaces. Optimization focuses on reducing power consumption, minimizing cost, improving performance, and ensuring compact design for real-world applications.

(d) Explain the Bluetooth communication between master and slave module in detail

In Bluetooth communication, the master controls the connection and data exchange, while the slave responds to commands. The master initiates pairing, synchronization, and data transfer. This setup is widely used in IoT for wireless data exchange between devices.

(e) Discuss the different way of packaging of IoT product in detail

IoT product packaging includes plastic enclosures, metal casings, waterproof housings, and modular packaging. Proper packaging ensures durability, protection from environmental factors, heat dissipation, and user safety.

SECTION C

Q3

(a) Discuss how Blynk app is used in IoT? Explain step by step

Steps:                                                                     Install Blynk app on smartphone

Create a new project                                             Select hardware and connection type

Add widgets (buttons, sliders, displays)                Get authentication token

Write Arduino code with Blynk library                   Upload code and control devices remotely

(b) Explain how GPS tracking device interfaced with IoT Board

A GPS module is connected to the IoT board using UART communication. The GPS module provides latitude and longitude data, which is processed by the controller and transmitted to cloud or mobile applications for real-time tracking.

Q4

(a) How temperature and gas sensor can be used together in an IoT system?

Temperature and gas sensors together provide environmental monitoring. Temperature sensors detect heat changes, while gas sensors detect harmful gases. Combined data helps in fire detection, industrial safety, and smart building monitoring systems.

(b) Explain the interfacing of Nokia 5110 in IoT system with suitable diagram

Nokia 5110 LCD is interfaced using SPI communication. It displays sensor data and system status.
(👉 Draw labeled block diagram in exam)

Q5

(a) Explain the different product realization techniques in IoT product development

Product realization includes concept design, prototyping, testing, optimization, manufacturing, and deployment. It ensures the product meets functional, safety, and market requirements.

(b) Draw and explain the flowchart of IoT warehouse monitoring system

Flow:
Start → Read sensors → Compare with threshold → Send data to cloud → Generate alerts → Display results → Repeat

Q6

(a) Explain the mechanism used in storing data on Google Sheet

IoT devices send data to cloud APIs using HTTP requests. Google Sheets API stores data in spreadsheet format for easy access, visualization, and analysis.

(b) Define ThingSpeak Cloud and its role in data visualization

ThingSpeak is an IoT cloud platform that stores sensor data and visualizes it using graphs and charts. It supports MATLAB analytics for advanced processing.

Q7

(a) Explain the main components of warehouse monitoring system

Components include sensors, microcontroller, communication module, cloud platform, mobile app, and alert system.

(b) Which packaging type is most used in IoT product and why?

Plastic enclosures are most used because they are lightweight, low-cost, corrosion-resistant, and easy to customize.