QBasic

Ch-7

QBASIC

class 8

Very short answer type questions:-

Q1. What is library function?

Ans1. Library functions in QBASIC are used for scientific and mathematical calculations. These are also called built in functions.

Syntax: - Function name (argument)

There are two types of library functions: -

1.       Numeric               2. String.

Q2. What do you mean by word ‘string’?

Ans2. String is a combination of a group of characters or words which are enclosed with in double quotes.

Q3. Explain SGN () function in brief.

Ans3. This function determines the sign of the given function. Eg: - SGN(-45) will return the value -1 and SGN(52) will return the  value 1.

Q4. Differentiate between RIGHT$() and LEFT$().

Ans4.

RIGHT$()	LEFT$()
This function returns the specified number of characters from the right most side of the string.	This function returns the specified number of characters from the left most side of the string.
Syntax: - RIGHT $(string, specific number of characters)	Syntax: - LEFT $(string, specific number of characters)
Example: - Right$ (software, 5) -> ware	Example: - Right$ (software, 5) -> soft

Q5. How the SOUND command is different from the PLAY command.

Ans5.

Sound	Play
SOUND command generates a sound through computer’s speaker	PLAY command is used for playing musical notes with the help of alphabetic characters.
Example: - SOUND 1000, 5	Example: - CLS                        PLAY”CDEFGAB”                        END

 Long answer type questions: -

Q1. Define loop. If we do not use the ‘STEP’ statement, what will happen?

Ans1. Loops include certain series of instructions which are to be repeated for a particular number of times or till the conditions are satisfied. If we do not use STEP statement, the for loop will by default increment the value by 1.

Q2. Write the difference between FOR NEXT LOOP and DO LOOP.

Ans2.

FOR NEXT	DO LOOP
The FOR NEXT statement instructs the computer to repeat a set of instructions for a given number of times.	It is a block of commands, where the program does not have to do something a certain number of times like in FOR NEXT.
Example: - CLS             Input ”Enter a name” ;  A$                       For    x = 1 to 5                       PRINT A$                       NEXT X                       END	Example: - CLS                    Sum = 0  INPUT ”Enter the first number (-1 to quit);” , Number                    LOOP       PRINT ”The sum is; “sum                    END