1 Exampromax - Stuvia US
GCSE COMPUTER SCIENCE PAPER 1:
ALL THEORY (EDEXCEL) Questions and
Answers 100% Correct Answers Already
Graded A+
Q: TOPIC 1: COMPUTATIONAL THINKING
Ans: TOPIC 1: COMPUTATIONAL THINKING
Q: Computational Thinking
Exampromax - Stuvia US
Ans: Process used to solve complex problems. It means formulating a problem
and expressing it's solution in such a way that a computer can carry it out
Q: Abstraction
Ans: Identifying the key parts of the problem and removing any unnecessary
detail so it becomes easier to solve
Q: Decomposition
Ans: Breaking down a complex problem into smaller, more manageable parts
which are easier to solve.
Q: What are subroutines?
Ans: Subroutines are small blocks of code in a modular program designed to
perform a particular task
Q: Decomposition creates subroutines. List some advantages of these.
Ans: -Makes debugging and maintaining the program easier
-Subroutines can be tested seperately and shown to be correct
-A particular subroutine can be called several times in the program
Q: What are flowcharts?
, 2 Exampromax - Stuvia US
Ans: A usefool tool that can be used to develop solutions to a problem. They
graphically represent steps in a problem
Q: What is pseudocode useful for?
Ans: Useful for developing an algorithm using programming-style constructs,
but it is not an actual programming language
Q: Why is pseudocode useful?
Ans: The programmer can concentrate on figuring out how to solve the problem
without worrying about the details of how to write each statement in the
programming language they will use
Q: Define algorithm
Ans: A sequence of steps that can be followed in order to complete a task
Exampromax - Stuvia US
Q: Explain the difference between an algorithm and a computer program.
Ans: A computer program is one way of implementing an algorithm in a
particular language (like python) but the algorithm is the series of instruction and
it's order
Q: What is a trace table used for?
Ans: Show how the values of variables change during the execution of the
program. As each line of code is executed, the current value of any variable that is
changed is written in the appropriate column on the table
Q: What is a syntax error and what does it do?
Ans: A syntax error will prevent your program from running. It is typically
caused by a mistake in the spelling or 'grammar' of the code.
Q: What is a logic error and what does it do?
Ans: A logic error may crash your program or produce an unexpected/incorrect
output. Logic errors occur due to things such as < or > symbols, or brackets,
which could affect loop conditions or range checks.
Q: What is a runtime error and what does it do?
, 3 Exampromax - Stuvia US
Ans: A runtime error is one which will be detected when the program is run. It
may be caused by a logic error, erroneous user input or by the program not
allowing for a condition such as a user inputting 0 or entering no data at all.
Division by 0 may also cause it.
Q: Name 2 search algorithms
Ans: Binary and Linear search
Q: What does a binary search do?
Ans: Can be used to search a list in numerical or alphabetical order. It works by
repeatedly dividing in half the portion of the list that could contain the required
data item
Q: What does a linear search do?
Exampromax - Stuvia US
Ans: In a linear search, the item will be checked one by one in the list. This is
very slow for large lists but necessary if the list is not sorted.
Q: Linear Search VS Binary Search
Ans: Linear:
- Inefficient but easy to implement
Binary:
-Very efficient and fast, but harder to implement and only works on sorted lists
Q: How does a bubble sort work?
Ans: It works by repeatedly going through the list to be sorted and swapping
adjacent elements if they are in the wrong order
Q: How does a merge sort work?
Ans: In the first stage, the list is succesively divided in half until each sublist is
the length of one. In the second stage each pair of sublists is repeatedly merged to
produce new sublists until one, final sorted list is produced.
Q: Bubble sort VS Merge sort
, 4 Exampromax - Stuvia US
Ans: Merge sort: More complex, recursive algorithm (it uses a subroutine that
calls itself). Many times faster for large data sets.
Bubble sort: Iterative algorithm, meaning it uses WHILE and/or FOR loops,
repeating the same step many times
Q: How is efficiency of an algorithm calculated?
Ans: The efficiency of an algorithm can be measured by the time it takes to
execute , or the amount of memory required for a given dataset.
Q: QUESTION: What are the benefits of using decomposition and
abstraction?
Ans: Decomposition breaks down a complex problem into subproblems, which
are much easier to solve, easier to understand and can also be examined in more
detail. Therefore, if a problem is not decomposed it is much harder to solve.
Exampromax - Stuvia US
Abstraction filters out unecessary information. Abstraction allows programmers
to create a general idea of what the problem is and how to solve it. The process
instructs them to remove all specific detail and any patterns that will not help find
a solution. An idea of the problem can then be formed. This idea is known as a
'model'
Q: TOPIC 2: DATA
Ans: TOPIC 2: DATA
Q: A computer is made up of...
Ans: Billons of switches, each with an off or on state.
Q: What is binary?
Ans: This is how the on/off is represented. off is 0 and on is 1.
Q: Why is binary important?
Ans: It is the only language computers can understand, so everything must be
converted into binary before being fed into a computer.
Q: There are two types of binary shift. Logical and arithmetic. What does a
logical shift do?
GCSE COMPUTER SCIENCE PAPER 1:
ALL THEORY (EDEXCEL) Questions and
Answers 100% Correct Answers Already
Graded A+
Q: TOPIC 1: COMPUTATIONAL THINKING
Ans: TOPIC 1: COMPUTATIONAL THINKING
Q: Computational Thinking
Exampromax - Stuvia US
Ans: Process used to solve complex problems. It means formulating a problem
and expressing it's solution in such a way that a computer can carry it out
Q: Abstraction
Ans: Identifying the key parts of the problem and removing any unnecessary
detail so it becomes easier to solve
Q: Decomposition
Ans: Breaking down a complex problem into smaller, more manageable parts
which are easier to solve.
Q: What are subroutines?
Ans: Subroutines are small blocks of code in a modular program designed to
perform a particular task
Q: Decomposition creates subroutines. List some advantages of these.
Ans: -Makes debugging and maintaining the program easier
-Subroutines can be tested seperately and shown to be correct
-A particular subroutine can be called several times in the program
Q: What are flowcharts?
, 2 Exampromax - Stuvia US
Ans: A usefool tool that can be used to develop solutions to a problem. They
graphically represent steps in a problem
Q: What is pseudocode useful for?
Ans: Useful for developing an algorithm using programming-style constructs,
but it is not an actual programming language
Q: Why is pseudocode useful?
Ans: The programmer can concentrate on figuring out how to solve the problem
without worrying about the details of how to write each statement in the
programming language they will use
Q: Define algorithm
Ans: A sequence of steps that can be followed in order to complete a task
Exampromax - Stuvia US
Q: Explain the difference between an algorithm and a computer program.
Ans: A computer program is one way of implementing an algorithm in a
particular language (like python) but the algorithm is the series of instruction and
it's order
Q: What is a trace table used for?
Ans: Show how the values of variables change during the execution of the
program. As each line of code is executed, the current value of any variable that is
changed is written in the appropriate column on the table
Q: What is a syntax error and what does it do?
Ans: A syntax error will prevent your program from running. It is typically
caused by a mistake in the spelling or 'grammar' of the code.
Q: What is a logic error and what does it do?
Ans: A logic error may crash your program or produce an unexpected/incorrect
output. Logic errors occur due to things such as < or > symbols, or brackets,
which could affect loop conditions or range checks.
Q: What is a runtime error and what does it do?
, 3 Exampromax - Stuvia US
Ans: A runtime error is one which will be detected when the program is run. It
may be caused by a logic error, erroneous user input or by the program not
allowing for a condition such as a user inputting 0 or entering no data at all.
Division by 0 may also cause it.
Q: Name 2 search algorithms
Ans: Binary and Linear search
Q: What does a binary search do?
Ans: Can be used to search a list in numerical or alphabetical order. It works by
repeatedly dividing in half the portion of the list that could contain the required
data item
Q: What does a linear search do?
Exampromax - Stuvia US
Ans: In a linear search, the item will be checked one by one in the list. This is
very slow for large lists but necessary if the list is not sorted.
Q: Linear Search VS Binary Search
Ans: Linear:
- Inefficient but easy to implement
Binary:
-Very efficient and fast, but harder to implement and only works on sorted lists
Q: How does a bubble sort work?
Ans: It works by repeatedly going through the list to be sorted and swapping
adjacent elements if they are in the wrong order
Q: How does a merge sort work?
Ans: In the first stage, the list is succesively divided in half until each sublist is
the length of one. In the second stage each pair of sublists is repeatedly merged to
produce new sublists until one, final sorted list is produced.
Q: Bubble sort VS Merge sort
, 4 Exampromax - Stuvia US
Ans: Merge sort: More complex, recursive algorithm (it uses a subroutine that
calls itself). Many times faster for large data sets.
Bubble sort: Iterative algorithm, meaning it uses WHILE and/or FOR loops,
repeating the same step many times
Q: How is efficiency of an algorithm calculated?
Ans: The efficiency of an algorithm can be measured by the time it takes to
execute , or the amount of memory required for a given dataset.
Q: QUESTION: What are the benefits of using decomposition and
abstraction?
Ans: Decomposition breaks down a complex problem into subproblems, which
are much easier to solve, easier to understand and can also be examined in more
detail. Therefore, if a problem is not decomposed it is much harder to solve.
Exampromax - Stuvia US
Abstraction filters out unecessary information. Abstraction allows programmers
to create a general idea of what the problem is and how to solve it. The process
instructs them to remove all specific detail and any patterns that will not help find
a solution. An idea of the problem can then be formed. This idea is known as a
'model'
Q: TOPIC 2: DATA
Ans: TOPIC 2: DATA
Q: A computer is made up of...
Ans: Billons of switches, each with an off or on state.
Q: What is binary?
Ans: This is how the on/off is represented. off is 0 and on is 1.
Q: Why is binary important?
Ans: It is the only language computers can understand, so everything must be
converted into binary before being fed into a computer.
Q: There are two types of binary shift. Logical and arithmetic. What does a
logical shift do?
