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Correct option is (d) Light DEPENDENT Resistor

Explanation: An LDR is called a Light Dependent Resistor. It is ALSO called a photo-resistor or a cadmium sulfide CELL. It is a photocell that WORKS on the principle of photo-conductivity. It’s resistance value decreases when the intensity of light decreases and vice-versa.

Right ANSWER is (b) Active

Easiest explanation: The MPU 6050 sensor is an active sensor since it requires an active DC voltage source to function PROPERLY. On the CONTRARY, an LDR can be said to be a sort of a passive sensor since it does not require the input of CURRENT from an external source for its working.

The correct choice is (b) Digital

Explanation: The TRIGGER pin is to be KEPT HIGH for a period of 10 MICROSECONDS meanwhile the ECHO pin is HIGH for the time period it takes for the sent Ultrasonic wave to return to the SENSOR. Thus, the entire detection is digital.

The correct answer is (a) Damage is caused

Best explanation: The OV7670 Camera Modules are mostly built to WORK on a VOLTAGE of approximately 3.3V. Any voltage LOWER than that and the sensor will not be able to POWER on, but HOWEVER any voltage significantly above that and the sensor may suffer permanent damage.

Correct answer is (C) 100 mA

To explain: The current rating on the ESP8266 WiFi Module is GIVEN so that users can know what is the optimum current that needs to be fed to the module such that the INTERNAL ELECTRONICS is not DESTROYED by excess current.

The correct CHOICE is (a) Damage is caused

The BEST explanation: The Relay modulesare mostly BUILT to work on a voltage RANGE of approximately 3.3V to 5V. Any voltage lower than that and the sensor will not be able to power on, but however any voltage significantly above that and the sensor may suffer permanent damage.

Correct choice is (a) Lead Sulfide

Easy explanation: What the LDR needs is a semiconductor. So that when some light having enough energy STRIKES on it, more electrons are excited to the conduction band which RESULTS in LARGE NUMBER of charge carriers which in turn results in current flowing through it when the circuit is CLOSED.

The CORRECT option is (b) 0.5V

Easiest explanation: A VOLTAGE of 0.5 v is applied ACROSS the terminals and the current passing through the body is recorded and finally the value of EDA is CALCULATED.

Right answer is (a) SLEEP Analysis

Explanation: The GSR SENSOR GIVES the electrodermal activity of the PERSON in the form of a convenient number. So, in real time it can be used to track sleep DEFECTS in patients.

The CORRECT choice is (a) SPI

Best explanation: The Nokia 5110 Graphical Display MODULE uses the SPI communication protocol. It means Serial Peripheral Interface and it ALLOWS only a single stream of data to be moved to and from the source and the deployment target.

The correct answer is (a) Qualcomm 8015

To elaborate: TheAdafruit FONA 3G+GPS BREAKOUT’s GPS capabilities is powered by the Qualcomm 8015 GPS MODULE. It enables GEOLOCATION services from the same device for all kinds of embedded and IOT APPLICATIONS. It can be CONTROLLED using the serial port.

The correct choice is (b) 12 mA

Explanation: The source current RATING on the ESP8266 WiFi Module is given so that users can know what is the MAXIMUM VALUE of the IO Source Current in the module such that the internal electronics is not destroyed by EXCESS current supplied.

Correct OPTION is (a) 28 A

The best explanation: The current rating on the RELAY Module is given so that USERS can know what is the optimum current that needs to be FED to the module such that the internal electronics is not destroyed by EXCESS current.

Right option is (C) BINARY Image

To explain I would say: Since the pixels of the NOKIA 5110 Graphical Display Module have only two states, that are either ON or OFF, it is able to only display binary bitmap images. So while feeding the image to the module, the image must be converted to binary with the help of preprocessing SOFTWARE.

Right ANSWER is (d) FLASH Mode

Easy explanation: UART Modegives the correct COMBINATION of input needed for the module to run the PROGRAM that is already uploaded to the module.

The correct option is (c) Micro Siemens

For explanation: The UNIT of skin CONDUCTANCE is micro Siemens. It works by applying a very small VOLTAGE ACROSS the two terminals of the sensor and then RECORDING the current passing through the body.

The CORRECT answer is (a) 5 to 10 ms

The explanation: 5 to 10 ms is the correct VALUE of the time needed for the MODULE to react to any command given to it by an external voltage SOURCE or micro-controller.

Right option is (d) SWITCHES circuits

The EXPLANATION is: The Motor Driver (L293D)Module is used for controlling motors by one micro-controller or when MANY motors must be CONTROLLED by one micro-controller.

The correct option is (a) AREA

For explanation: The ADXL-335 Accelerometer sensor uses capacitive technology to carry out its functions. I the EQUATION C=f(A/d), ‘A’ stands for the area of the PLATE, and the ‘d’ stands for the distance of SEPARATION between the two plates.

Right option is (b) 15 mA

For explanation I would say: The current RATING on any Sensor is GIVEN so that USERS can KNOW what is the optimum current that needs to be fed to the active sensor such that the internal electronics is not DESTROYED by excess current.

The correct choice is (a) Proximity Detection

Best explanation: The Ultrasonic SENSOR is used for calculating the distance between the sensor and the object. It is mostly used for calculating the acceleration, velocity and position of the sensor attached to the DEVICE. It basically has two TERMINALS which emit an Ultrasonic Signal and RECEIVE the emitted Ultrasonic Signal. The time difference between these two gives us the required data for such calculations.

Right option is (a) theta=atan(X_Value/sqrt((Y_Value*Y_Value)+(Z_Value*Z_Value)))

For EXPLANATION I would say: atan(X_Value/sqrt((Y_Value*Y_Value)+(Z_Value*Z_Value))) gives the correct value of the angle of inclination of the accelerometer MODULE. Here all the three values read from the 3 data pins of the ADXL-335 module are to be REPLACED in the EQUATION at the same time in order for this to work.

The CORRECT option is (d) Sound

Best explanation: The Ultrasonic Sensor WORKS on Ultrasonic Sound Waves. These sound Waves are very powerful and have a very HIGH FREQUENCY which results in low attenuation.

The correct option is (b) Digital

To explain I would SAY: The DC pin of the Nokia 5110 Graphical DIsplay Module ACCEPTS only binary INPUT wherein 0 means that sending 0 or a logical LOW SIGNAL will prime the module to accept system commands while sending a 1 or a logical HIGH signal will prime the module to accept actual display data.

Correct option is (a) VARIOPIXEL

The EXPLANATION: VarioPixel is the correct NAME of the sub-sampling TECHNOLOGY used by theOV7670 Camera MODULE. Sub-sampling in image processing is the process of reducing the image size by removing information all together.

The CORRECT choice is (c) Parallel Digital

The explanation is: The output format in theOV7670 Camera MODULE is Parallel Digital. This is DUE to the fact that it has 8 pins dedicated to video output marked from D0 to D7 on the module which are to be CONNECTED to the Arduino for the output.

The CORRECT choice is (b) Anticlockwise MOTOR Rotation

Explanation: Anticlockwise motor rotationgives the correct LOGIC sequence which enables the micro-controller to turn one SET of MOTORS anticlockwise. This is true for the other set too.

The correct answer is (b) Object is oscillating side by side

To elaborate: The only explanation for such output from the SENSOR would be if the object is moving in such a PATH, that makes it WITHIN the range of the sensor and VICE versa after each specified amount of time and this continuously happens along a deterministic path so that we know that the only way this can happen is that if the object is oscillating between two given POINTS.

Correct choice is (b) Active

For explanation I would say: The ADXL-335 sensor is an active sensor since it requires an active DC voltage source to function PROPERLY. On the contrary, an LDR can be said to be a sort of a passive sensor since it does not require the INPUT of current from an EXTERNAL source for its working.

Right option is (a) Damage is caused

The BEST I can explain: The Nokia 5110 Graphical Display Modulerequires you to apply a pulse to the RST PIN which clears all the internal registers and primes the module to START accepting new commands. So it is always NECESSARY to WIPE out the residual data.

The correct answer is (B) 8

For explanation I would say: The Nokia 5110 Graphical Display Module has 8 pins based on the internal architecture of it’s microcontroller. The pins are Vcc which supplies voltage and powers the entire module, GND which completes the CIRCUIT, RST which resets the module’s display, CE, which enables communications to the onboard CHIP of the module, DCand Dinis used to send data commands, Clk which is the clock pin, and BL which enables or disables the backlight of the display module.

Correct OPTION is (C) Network Provider

The best I can explain: The ESP8266 WiFi Module is BASICALLY a network provider module which helps your micro-controller to CONNECT to any WiFi network in the vicinity.

Right choice is (a) Analog

The explanation is: The SIG pin gives US the actual data RECEIVED by the sensor, and SINCE the VALUE can FLUCTUATE very easily it is an Analog pin.

Right CHOICE is (a) Infrared

To explain: The IR Sensor works on Infrared waves. These waves have a LONGER wavelength than visible light and are a form of electromagnetic RADIATION. Usually Infrared can be felt as heat when incident on humans, but the sensor’s intensity is too SMALL to be felt usually.

Right answer is (C) AT COMMANDS

For explanation I would say: The Adafruit FONA 3G+GPS Breakout accepts AT commands which can be provided from any computer that is connected to it. AT Commands are an abbreviation for ATTENTION Commands which are generally USED for manipulating different types of modems.

The correct option is (d) IMAGE Capture

For explanation I would say: The OV7670 CAMERA Module is basically an image capturing device which is designed for use in embedded SYSTEMS. It uses a 3.3V Power supply and an external oscillator provides the clock source for the XCLK PIN.

The correct OPTION is (d) Circuit Completion

The explanation is: The COM pin is used for completing the circuit such that the RELAY MODULE can function fully when CONNECTED to the micro-controller. There are 2 COM PINS, 1 for each channel.

Right choice is (a) DAMAGE is caused

For explanation: The MPU 6050 Sensors are mostly built to work on a voltage range of approximately 3.3V to 5V. Any voltage lower than that and the sensor will not be ABLE to power on, but however any voltage SIGNIFICANTLY above that and the sensor may suffer PERMANENT damage.

Correct ANSWER is (a) Monitors MOTION

To elaborate: The MPU 6050 Sensor is a complete motion tracking DEVICE which comes equipped out of the box with a gyroscope for tracking tilt, ROLL, etc.. , ACCELEROMETER for tracking motion, and a temperature sensor.

Correct ANSWER is (a) Damage is caused

Easiest EXPLANATION: The IR Sensors are mostly BUILT to work on a VOLTAGE range of approximately 3.3V to 5V. Any voltage lower than that and the sensor will not be able to power on, but however any voltage significantly above that and the sensor may SUFFER permanent damage.

The CORRECT ANSWER is (b) To DISPLAY something

Explanation: The Nokia 5110 Graphical Display Module is USED to display various texts, images, and PATTERNS. It is not a sensor so it cannot sense anything, but it gives an output, from a controlled signal so it behaves more like a transducer.

Right choice is (b) No

The best explanation: The OV7670 Camera Module has a voltage RATING of 3.3V so if we are to CONNECT it to the 5V Arduino output, it will damage the INTERNAL circuit for the module. So we need to add a POTENTIAL divider in the area to bring the voltage down.