COMPUTER SCIENCE AQA A-LEVEL PAPER 1 ACTUAL EXAM |
QUESTIONS AND ANSWERS | VERIFIED ANSWERS (100%
CORRECT) | LATEST EXAM UPDATE
What is an integer?
A positive or negative whole number
What is a Real or Float number?
A positive or negative number that can have a fractional part.
What is a Boolean?
True or False
What is a character?
A single letter, number or symbol
What is a string?
A group of characters
What is Date/Time?
A way of storing Date/Time
What is a pointer?
A way of storing a memory address.
What is a record?
A collection of related fields, each of which could hold a different data type.
What is an array?
A finite, indexed set of related elements of the same data type.
What is a user defined data type?
A data type derived from existing data types in order to create a
customized data structure.
What is variable declaration?
Creating a variable for the first time. giving it a name and sometimes a
data type.
What is constant decleration?
,Creating a constant for the first time.
What is assignment?
giving a constant or a variable a value.
what is iteration?
repetition of a process e.g. a while or for loop. this could be definite or
indefinite.
What is selection?
comparing values and then choosing an appropriate action. e.g. an if
statement.
what is a subroutine?
A named block of code containing a set of instructions designed to perform
a frequently used operation.
What is definite iteration?
the number of repititions is known before the loop starts.
What is indefinite iteration?
the number of repititions is not known before the loop starts.
What is a nested structure?
One structure is placed within another. Easily identified by indentation.
What is meant by meaningful identifier names?
Giving constants, variables and subroutines sensible and meaningful
identifier names.
What does the real/float division operator do?
divides one number by the other.
What does the integer division operator do?
divides one number by the other but only returns the whole number part.
What does the modulo operator do?
returns the remainder of an integer division.
What does the exponentiation operator do?
raises one value to the power of another.
,What does the rounding operator do?
limits the degree of accuracy of a number. (rounds up or down)
What does the truncation operator do?
removes the decimal part of a number. (never rounds up)
what does the string handling function "Length" do?
Returns the number of characters in a specified string.
what does the string handling function "position" do?
returns the position of a specified character within a string.
what does the string handling function "concatenation" do?
joins two or more strings together to form a new and longer string.
Is a function required to return a value?
yes
is a procedure required to return a value?
no
what can stack frames store for each subroutine?
Return addresses
Parameters
Local variables
what is a recursive subroutine?
a subroutine defined in terms of itself.
what two conditions must a recursive subroutine meet in order for the
program to run correctly.
it must have a stopping condition/base case.
this stopping condition must be met at some point.
what type of error would occur if a base case in a recursive subroutine is
never met.
Stack overflow error.
what is a data type?
, a particular kind of data item, as defined by the values it can take, the
programming language used, or the operations that can be performed on it.
why is it important to give meaningful identifier names?
It allows a different programmer to work out the purpose of a constant,
variable or subroutine from its name.
what two things are data types defined by?
there values they can take and the operations that can be performed on
them.
is -44 an integer?
yes
which data type can only be true or false?
Boolean.
in what type of iteration is the number of repititions required not known
before the loop starts?
Indefinite iteration
what visible feature of program code signifies nesting?
indentation.
using INTEGER division what is 14 DIV 3
4
using the modulo operation what is 30 MOD 4?
2
What is 1 XOR 1?
0
Name two advantages of using constants over hard coded values.
Constants can be given identifier names, making the code easier to
understand for humans.
When updating the code constants only need updating at one position in
code.
what is a seed value used for?
generating random numbers.
QUESTIONS AND ANSWERS | VERIFIED ANSWERS (100%
CORRECT) | LATEST EXAM UPDATE
What is an integer?
A positive or negative whole number
What is a Real or Float number?
A positive or negative number that can have a fractional part.
What is a Boolean?
True or False
What is a character?
A single letter, number or symbol
What is a string?
A group of characters
What is Date/Time?
A way of storing Date/Time
What is a pointer?
A way of storing a memory address.
What is a record?
A collection of related fields, each of which could hold a different data type.
What is an array?
A finite, indexed set of related elements of the same data type.
What is a user defined data type?
A data type derived from existing data types in order to create a
customized data structure.
What is variable declaration?
Creating a variable for the first time. giving it a name and sometimes a
data type.
What is constant decleration?
,Creating a constant for the first time.
What is assignment?
giving a constant or a variable a value.
what is iteration?
repetition of a process e.g. a while or for loop. this could be definite or
indefinite.
What is selection?
comparing values and then choosing an appropriate action. e.g. an if
statement.
what is a subroutine?
A named block of code containing a set of instructions designed to perform
a frequently used operation.
What is definite iteration?
the number of repititions is known before the loop starts.
What is indefinite iteration?
the number of repititions is not known before the loop starts.
What is a nested structure?
One structure is placed within another. Easily identified by indentation.
What is meant by meaningful identifier names?
Giving constants, variables and subroutines sensible and meaningful
identifier names.
What does the real/float division operator do?
divides one number by the other.
What does the integer division operator do?
divides one number by the other but only returns the whole number part.
What does the modulo operator do?
returns the remainder of an integer division.
What does the exponentiation operator do?
raises one value to the power of another.
,What does the rounding operator do?
limits the degree of accuracy of a number. (rounds up or down)
What does the truncation operator do?
removes the decimal part of a number. (never rounds up)
what does the string handling function "Length" do?
Returns the number of characters in a specified string.
what does the string handling function "position" do?
returns the position of a specified character within a string.
what does the string handling function "concatenation" do?
joins two or more strings together to form a new and longer string.
Is a function required to return a value?
yes
is a procedure required to return a value?
no
what can stack frames store for each subroutine?
Return addresses
Parameters
Local variables
what is a recursive subroutine?
a subroutine defined in terms of itself.
what two conditions must a recursive subroutine meet in order for the
program to run correctly.
it must have a stopping condition/base case.
this stopping condition must be met at some point.
what type of error would occur if a base case in a recursive subroutine is
never met.
Stack overflow error.
what is a data type?
, a particular kind of data item, as defined by the values it can take, the
programming language used, or the operations that can be performed on it.
why is it important to give meaningful identifier names?
It allows a different programmer to work out the purpose of a constant,
variable or subroutine from its name.
what two things are data types defined by?
there values they can take and the operations that can be performed on
them.
is -44 an integer?
yes
which data type can only be true or false?
Boolean.
in what type of iteration is the number of repititions required not known
before the loop starts?
Indefinite iteration
what visible feature of program code signifies nesting?
indentation.
using INTEGER division what is 14 DIV 3
4
using the modulo operation what is 30 MOD 4?
2
What is 1 XOR 1?
0
Name two advantages of using constants over hard coded values.
Constants can be given identifier names, making the code easier to
understand for humans.
When updating the code constants only need updating at one position in
code.
what is a seed value used for?
generating random numbers.
