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Correct ANSWER is (c) To denote the most significant bit

To explain I WOULD say: The shiftIn() function shifts in one byte of a binary number bit by bit starting from either the most significant bit or the least significant bit. Now after each bit is pulled, the CLOCK pin is turned to HIGH until the next one at which point the clock pin is turned down to LOW again. Now the MSBFIRST argument denotes that the byte of data be read from left to right.

Correct choice is (b) 2

To explain I would SAY: The digitalWrite() function can be used to send out two VOLTAGE levels; 0V and 5V which correspond to the digital LOW signal and the digital HIGH signal respectively. These voltage levels can however vary from board to board. For example, in some Arduino Boards the digital HIGH signal corresponds to 3.3V instead of 5V. Hence even if the voltage levels are different here, the meaning of the signal REMAINS the same.

The correct OPTION is (a) EEPROM.h

Best explanation: The EEPROM is a type of memory in microcontrollers that is ABLE to retain the data that was FED to it even after the power supply is CUT off from the chip.The EEPROM.h library allows us to perform read, WRITE, clear, updating, etc. operations on the EEPROM of our Arduino Board. This is a standard library that can be used for all Arduino Boards.

Right answer is (c) INFINITELY till the POWER is supplied to the Arduino

Easy EXPLANATION: The loop() function is generally used to carry out most of the calculations that are required to sustain the working of the Arduino project. It is preprogrammed to run CONTINUOUSLY once the Arduino is successfully BOOTED and the setup() function has been executed once.

The CORRECT choice is (a) Yes

To explain: The PROGMEM Utility can be USED with non-static variables provided they are defined outside any function, i.e. they are defined GLOBALLY. Conversely if one needs to WORK on a variable that is not defined globally then they would NEED to convert that variable into a static variable in order to use the PROGMEM Utility.

The correct option is (d) Converting a VARIABLE from ONE type to another

Explanation: Casting is the PROCESS of forcefully converting a variable from one data type to another. There are 4 types of casting; static CAST, dynamic cast, const cast, reinterpret cast.

The correct answer is (c) 2

To explain: The strcpy() function is used to COPY the contents from one String variable to another. Hence it requires a minimum of TWO arguments that INCLUDE the source variable (The variable from WHOSE contents NEED to be copied from) and the destination variable (The variable to which the contents are to be copied to).

Correct answer is (a) To find the cosine of a number

The explanation is: The COS() function is used to find the cosine of a number. It takes one argument; the number whose cosine is to be found out. This number is to be ENTERED in the radian format and not the degree format. This function can accept any number-based datatypes and GIVES the output in the DOUBLE DATATYPE.

Right answer is (C) The max() FUNCTION

To explain: The max() function takes in 2 arguments and outputs only 1 NUMBER. This function finds out the MAXIMUM of the 2 numbers that are ENTERED as arguments to the function. This function is essential in sorting techniques.

The correct option is (c) 3

For EXPLANATION: The pulseIn() FUNCTION is used to determine the length of a pulse supplied to a digital pin. It generally accepts two arguments; the pin NUMBER, and the state, i.e. HIGH or LOW. If the state is given as HIGH, then it will wait for the pin to go HIGH and then start counting the time TILL the pin returns back to LOW. Here the length of the pulse is given by the function in microseconds.

Correct choice is (C) 5V/1024

The best explanation: The Arduino converts all analog voltages (0V to 5V or 3.3V) taken as INPUT into a range of 0 to 1023. This is done by mapping the voltage LEVELS. On the Arduino Uno the MAXIMUM voltage level is 5V and the onboard ADC has a resolution of 10 bits which means it can divide the analog signal it receives into 210 levels.

The correct choice is (c) The compiler

For explanation: This is also CALLED type promotion and is carried out AUTOMATICALLY by the compiler wherein it automatically converts a variable from one DATA type to another data type which is HIGHER than that. Usually this is done to avoid any loss of data during calculations of floating type NUMBERS.

Correct OPTION is (c) 5

Easiest explanation: The map() function is used to map a NUMBER from one number set to another number set. It takes THREE arguments; the number to be mapped, the LOWEST number of the source number set, the highest number of the source number set, the lowest number of the destination number set, the highest number of the destination number set.

The CORRECT choice is (a) Yes, it can be called recursively

To explain: The ARDUINO Programming Language is a working SUBSYSTEM of the C++ Programming Language. This allows for any function to be called recursively at any point in the program. Since the LOOP() function is a custom predefined function in the Arduino Ecosystem, it too has to follow that rule.

The CORRECT answer is (c) #

Easy EXPLANATION: Any special commands that need to be executed by the preprocessor is always initialized with the help of the ‘#’ symbol. This helps in ENHANCING the clarity of the code that the programmer WRITES and also makes it easier for the preprocessor to complete it’s job faster SINCE it does not have to process each and every token throughout the program to simply find out what are the preprocessor commands that have been used.

The correct OPTION is (c) No

To explain I would SAY: The break statement is almost never used for aborting the execution of a program. It was designed for EXITING looping structures and shifting the CONTROL to the next scope available. The control statement that helps with that is the exit function.

The CORRECT choice is (c) Yes, it can be used

Easy explanation: The digitalRead() FUNCTION basically READS voltage differences of 0V and 5V which correspond to 0 and 1023, in the ArduinoEcosystem. This can be recreated using the analogRead() function to CHECK whether there is a voltage across the pin that CORRESPONDS to 0 and 1023 on the Arduino.

Right choice is (d) RECEIVING MESSAGES from the particular device

To elaborate: The dmesg command is used for displaying any messages like errors or warnings that a device might have issued to the system. It can give US 3 THINGS; the time, i.e. the time after startup when the message was generated, the device name, and the message text or message content.

The correct ANSWER is (c) #error

For EXPLANATION I would say: The #error directive first THROWS an error to the ARDUINO IDE which is then DISPLAYED and then the compilation process is stopped prematurely. This is used to enable the user to stop the compilation process programmatically if some criteria or condition is not met before he or she can allow the program to start running.

Correct OPTION is (c) The Arduino code is processed by a compiler

The best I can explain: The Arduino code is a working subset of the C++ programming language. The C++ programming language is a COMPILED one, not an interpreted language. The main difference between an interpreter and a compiler is the way that each one of them handles the debugging and execution of the code. A compiler first checks if the code has any SYNTAX errors or not and then PROCEEDS to converting or more appropriately translating the written code into assembly, while the interpreter executes the code LINE by line irrespective of whether there is any syntax error in the code or not.