Computer Science ) (Solved Questions 100% VERIFIED QUESTIONS AND ANSWERS)
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Course
Computer Science
Institution
Computer Science
optical media ANS:better known as music and film storage formats, CDs and DVDs are methods of digital information and data storage that can hold information of many types. one of the key uses 8is for software distribution. called optical media because they are written and read by laser.
paper ANS:...
A-Level AQA Computer Science Paper
2
Baud Rate ANS:The maximum possible number of signal changes that can occur in a wire per second.
Bit Rate ANS:The number of bits that can be sent down a wire per second.
Integer ANS:A whole number that can be positive, negative or zero.
Examples: -3, 0, 7, 2013588.
Natural (Number) ANS:A whole number that is either positive or zero.
Examples: 0, 1, 2, 100, 67238.
Rational (Number) ANS:Any number that can be represented as the fraction 'a/b' where 'a' and 'b' are
both integers.
Examples: -0.2, 4/5, 1, 1/3.
Irrational (Number) ANS:Any number that cannot be represented as a fraction.
Examples: square root of 2, PI.
Real (Number) ANS:Any number that can either be rational or irrational.
Boolean ANS:A value that is either true or false.
String ANS:A series of characters.
Array ANS:A variable that can store multiple values of the same data type.
Example: Storing the high-scores of a game as integers.
Record ANS:A variable that can store multiple values that can have different data types.
,Example: Storing data about a book; a string for the title, an integer for the number of pages, etc.
Variable ANS:A metaphor for it is that is a box that can store a specific type of item (the data type) and
has a name assigned to it (the identifier). Its value can be changed during run-time of the program.
Constant ANS:A metaphor for it is that is a box that can store a specific type of item (the data type) and
has a name assigned to it (the identifier). Its value cannot be changed during run-time of the program.
Subroutine ANS:This can be broken down into procedures and functions.
Procedure ANS:A block of code that performs a specific task that does not return a value. Parameters
can be passed into it.
Function ANS:A block of code that performs a specific task that returns a value. Parameters can be
passed into it.
Selection ANS:This is when an if statement or select case is used to, for example, check the value of a
variable.
Iteration ANS:This is when, within the program, there is a loop.
Definite Iteration ANS:The number of times that the program will loop is already specified.
Example: For loop.
Indefinite Iteration ANS:The number of times the program will loop is unknown.
Example: Do loop.
Nested (structures) ANS:This is when either iterative or selective statements are put inside of each
other.
Meaningful Identifiers ANS:Subroutines, variables and objects should have sensible names.
Real Division ANS:Finds the value (usually as a decimal) of one number divided by another.
Integer Division ANS:Finds the integer part of one number divided by another.
Integer Remainder ANS:Finds the remainder of one number divided by another.
Truncation ANS:Chops the decimal part off a number.
Floor ANS:Rounds a number down to the nearest integer.
, Ceiling ANS:Rounds a number up to the nearest integer.
AND ANS:Logical Operation:
Returns true only when both values are true.
OR ANS:Logical Operation:
Returns true as long as at least one of the values are true.
XOR ANS:Logical Operation:
Returns true only when exactly one of the two values is true and not both.
NOT ANS:Logical Operation:
Returns true if the value is false and returns false if the value is true.
Exception Handling ANS:When a try catch is used in the program to deal with any errors that may occur.
ByVal ANS:When a variable is passed into a subroutine as a copy so its value will not be changed.
ByRef ANS:When a variable is passed into a subroutine as a reference so its value can be changed.
Local (Variable) ANS:A variable that is defined, for example, within a subroutine and cannot be viewed
or modified from outside of the block of code is was declared in.
Global (Variable) ANS:A variable that is declared, usually at the start of the program, and can be
accessed and modified from anywhere at all in the program.
Recursion ANS:A subroutine's definition contains a self-call meaning a function or procedure calls itself
as a way of performing iteration.
Object-Oriented (Programming) ANS:A type of programming paradigm when multiple objects are
created and handled to run the program.
Example: In a game you might have an object for the player and then multiple objects for the enemies.
Procedural (Programming) ANS:A type of programming paradigm when you break down a project,
usually using a decomposition diagram, into individual tasks which can each be performed by a
procedure.
Functional (Programming) ANS:A type of programming paradigm that is mainly used for calculations. No
variables are declared, only functions are used with parameters and return statements.
(Object) Instantiation ANS:When an object is first created using the 'new' keyword.
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