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Official OCR Computer Science A451/01 Exam Thread

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Original post by s4b3rt00th
You could still refer to it by saying that RAM (sat nav itself has RAM) is volatile, therefore you would need a secondary storage to store data so that it can be used later after the power is switched off.


yep that's what I meant, thanks
For the question that asked why a solid state drive is better than a magnetic drive for a sat nav, I put that it is very compact so it will easily fit in the sat nav. Is this right?
These are rough approximations of the questions, not word for word
Question 1: Sat nav I/O
What is a computer system?[2]
-A system containing electronic devices that have software and hardware working together
-It is an electronic data processing machine that can take inputs and output results
Why does a computer system need input devices?
-To have data to process
Give an example of an input device for the sat nav for a disabled person and explain how it is useful.
-Keyboard? Mic?
Why does the satnav need a secondary storage device?[2]
-store maps, previous locations etc.
Why solid state storage?
-Portable-small, light
-withstand movement, no moving parts
Why are the commands stored as binary?
-1 and 0 can easily be represented via on and off signals. It allows easy simple logic gates. It allows less error as there are only two values
Name a task carried out by the CPU:[1]
-To fetch/execute commands from memory
-To decode commands
-To carry out the fetch, decode, execute cycle
-Perform Logic operations

Question 2: HTML and internet
What else might be in an HTML file other than text for the webpage?[2]
-image references
-cascading style sheets, CSS
-video references
One reason why is it good for HTML to be a standard?[2]
-All webpages are the same (pretty much) so browsers only have to support html
-People can have gaurenteed support for their webpage
-Other languages can be implemented effectively such as php, javascript and xml
Hexadecimal[2]
- 58 = 3A, 156 = 9C
Another question ??
How does the DNS connect the user to a webpage from the URL?[3]
The DNS has access to a database and associates the URL with a specific IP address. This can access the files and connect the user to the IP which also allows the DNS to contact the correct website.

3: Algorithm (I think)
Fill in the gaps[2]
-'count' and 'Total / Quantity)
What is a constant and give an example?[2]
-A value stored in a specific memory location represented by a name. The value cannot be changed while the program is running
E.g. Quantity
What data type is the Mean?[2]
-Real as it could be a decimal.
What other two types of iteration are there other than For?[2]
-while
-repeat/do until ?
It gives an example of a validation algorithm, Give an example of a boundary value and an invalid value.[2]
-100 or 0 are boundaries
-anything not between 0 and 100 inclusive are invalid values

4: Databases
Why is a database a persistent organised store of data?[2]
-It is a structured object that contains data. It is stored in tables. (Not sure about this one)
What is a suitable data type for the ID?[2]
-Text, as it has leading zeros
How many records are there[1]
-four
Which field is the primary key?[2]
-The first field, it is unique and follows the same format. It is a short number.
Name a validation method for TeacherID and Date, they must be different.
-TeacherID, follow format Letter,Letter,ID, or must be length three etc
-Date, follow format DD/MM/YYYY or it must be less than or equal to the current date
Name two features of a DBMS that allow you to make customizable applications.[6]
-Query, ask for records with certain attributes easily, e.g this lets the admin create a query for all outstanding repairs
-Form, create a GUI to make it easier to make a query, e.g. admin enters teachers ID into search box to get their repairs.

Question 5: Cars
Describe the ethical and legal issues surrounding the development of automatic technology such as driverless cars.[6]
-Cars follow the law always and may not cope in an emergency situation and therefore cause harm.
-Cars and automatic devices collect data perhaps unethically or illegally
-Automation increases unemployment, not right for robots to 'take over'
-Security required and so could break the data protection Act
-Hackability, could break the computers misuse act
Question 6: OCR accounts
Two advantages of a network in the office over standalone PCs:[6]
-Share expensive peripherals. All users can use the peripherals plugged in to any PC. This saves money as only one peripheral is needed and all the computers have access saving time.
-Share data/resources/programs. This allows quicker sharing of data and ideas over methods such as email. It is cheaper as users do not have to use physical storage devices to transfer data. Saves time as users do not have to take so long copying files as they are in a shared folder.
Name a piece of hardware to get an internet connection. Usually OCR accepts:[1]
-Router, modem (modulator-demodulator) or ADSL adapter
Name two other pieces of hardware for a network and explain:[4]
-Router/modem/ADSL, internet connection
-Hub, connect the devices for sharing
-NIC, allows connection via Ethernet or wireless
-Server, dedicated machine to supply data to clients etc.
-switches, like a hub but faster
Network policies:[6]
-Acceptable Use: User priviliges, malware protection etc
-Backup
-Failover
-Disaster Recovery
-Archive

Pseudocode:[6]
the criteria were
Use iteration
Have a previously stored number to guess
allow ten guesses
say to guess higher or lower
ask the user to guess
say congratulations and end the game if they guess it

I guess that it is one mark per criteria

approximately
Const Value = random number
count = 0
Ouput 'Guess the number'
Repeat
Output 'enter a number'
Guess = Input
If Guess = Value Then
Output 'Congratulations'
END
If Guess > Value THEN
Output 'guess higher'
if guess < Value then
Output 'Guess lower'
count = count + 1
Repeat until count = 10
output 'Sorry you did not guess the number. It was' + value
END


If anyone else has question answers contribute to help update the full markscheme
(I tried to add the number of marks but I don't remember all)
(edited 6 years ago)
revision
Original post by SamwiseGaMLGee
It was pretty hard, everything i was confident on didnt come up


I know. Looking at the revision guide afterwards on the content page, there was only about 3 questions across my strongest 3 topics- software, hardware, and date rep.
belly
I thought the exam was alright, it was't too hard.
Original post by CBoateng
These are rough approximations of the questions, not word for word
Question 1: Sat nav I/O
What is a computer system?[2]
-A system containing electronic devices that have software and hardware working together
-It is an electronic data processing machine that can take inputs and output results
Why does a computer system need input devices?
-To have data to process
Give an example of an input device for the sat nav for a disabled person and explain how it is useful.
-Keyboard? Mic?
Why does the satnav need a secondary storage device?[2]
-store maps, previous locations etc.
Why solid state storage?
-Portable-small, light
-withstand movement, no moving parts
Why are the commands stored as binary?
-1 and 0 can easily be represented via on and off signals. It allows easy simple logic gates. It allows less error as there are only two values
Name a task carried out by the CPU:[1]
-To fetch/execute commands from memory
-To decode commands
-To carry out the fetch, decode, execute cycle
-Perform Logic operations

Question 2: HTML and internet
What else might be in an HTML file other than text for the webpage?[2]
-image references
-cascading style sheets, CSS
-video references
One reason why is it good for HTML to be a standard?[2]
-All webpages are the same (pretty much) so browsers only have to support html
-People can have gaurenteed support for their webpage
-Other languages can be implemented effectively such as php, javascript and xml
Hexadecimal[2]
- 58 = 3A, 156 = 9C
Another question ??
How does the DNS connect the user to a webpage from the URL?[3]
The DNS has access to a database and associates the URL with a specific IP address. This can access the files and connect the user to the IP which also allows the DNS to contact the correct website.

3: Algorithm (I think)
Fill in the gaps[2]
-'count' and 'Total / Quantity)
What is a constant and give an example?[2]
-A value stored in a specific memory location represented by a name. The value cannot be changed while the program is running
E.g. Quantity
What data type is the Mean?[2]
-Real as it could be a decimal.
What other two types of iteration are there other than For?[2]
-while
-repeat/do until ?
It gives an example of a validation algorithm, Give an example of a boundary value and an invalid value.[2]
-100 or 0 are boundaries
-anything not between 0 and 100 inclusive are invalid values

4: Databases
Why is a database a persistent organised store of data?[2]
-It is a structured object that contains data. It is stored in tables. (Not sure about this one)
What is a suitable data type for the ID?[2]
-Text, as it has leading zeros
How many records are there[1]
-four
Which field is the primary key?[2]
-The first field, it is unique and follows the same format. It is a short number.
Name a validation method for TeacherID and Date, they must be different.
-TeacherID, follow format Letter,Letter,ID, or must be length three etc
-Date, follow format DD/MM/YYYY or it must be less than or equal to the current date
Name two features of a DBMS that allow you to make customizable applications.[6]
-Query, ask for records with certain attributes easily, e.g this lets the admin create a query for all outstanding repairs
-Form, create a GUI to make it easier to make a query, e.g. admin enters teachers ID into search box to get their repairs.

Question 5: Cars
Describe the ethical and legal issues surrounding the development of automatic technology such as driverless cars.[6]
-Cars follow the law always and may not cope in an emergency situation and therefore cause harm.
-Cars and automatic devices collect data perhaps unethically or illegally
-Automation increases unemployment, not right for robots to 'take over'
-Security required and so could break the data protection Act
-Hackability, could break the computers misuse act
Question 6: OCR accounts
Two advantages of a network in the office over standalone PCs:[6]
-Share expensive peripherals. All users can use the peripherals plugged in to any PC. This saves money as only one peripheral is needed and all the computers have access saving time.
-Share data/resources/programs. This allows quicker sharing of data and ideas over methods such as email. It is cheaper as users do not have to use physical storage devices to transfer data. Saves time as users do not have to take so long copying files as they are in a shared folder.
Name a piece of hardware to get an internet connection. Usually OCR accepts:[1]
-Router, modem (modulator-demodulator) or ADSL adapter
Name two other pieces of hardware for a network and explain:[4]
-Router/modem/ADSL, internet connection
-Hub, connect the devices for sharing
-NIC, allows connection via Ethernet or wireless
-Server, dedicated machine to supply data to clients etc.
-switches, like a hub but faster
Network policies:[6]
-Acceptable Use: User priviliges, malware protection etc
-Backup
-Failover
-Disaster Recovery
-Archive

Pseudocode:[6]
the criteria were
Use iteration
Have a previously stored number to guess
allow ten guesses
say to guess higher or lower
ask the user to guess
say congratulations and end the game if they guess it

I guess that it is one mark per criteria

approximately
Const Value = random number
count = 0
Ouput 'Guess the number'
Repeat
Output 'enter a number'
Guess = Input
If Guess = Value Then
Output 'Congratulations'
END
If Guess > Value THEN
Output 'guess higher'
if guess < Value then
Output 'Guess lower'
count = count + 1
Repeat until count = 10
output 'Sorry you did not guess the number. It was' + value
END


If anyone else has question answers contribute to help update the full markscheme
(I tried to add the number of marks but I don't remember all)


Yes, thank you for adding the marks number to my markscheme I couldn't remember them all.
Reply 47
Shame that calculation questions were practically non existent had to do a German exam and be kept inside because of an exam clash so writing was the last thing I wanted to do.

but all hail the data protection act, comes up every paper.
Meh it was alright I guess, pretty hard but based on these answers, I think there'll be a fair bit of leeway
I really do hope grade boundaries for both coursework and the paper are low like last year. If everyone did better on the paper AND coursework then I am ****** for sure.
I was quite disappointed that nothing about translators or binary gates and all that sort of stuff came up
(edited 6 years ago)
Original post by DarthYoda
These are rough approximations of the questions, not word for word
Question 1: Sat nav I/O
What is a computer system?
-A system containing electronic devices that have software and hardware working together
-It is an electronic data processing machine that can take inputs and output results
Why does a computer system need input devices?
-To have data to process
Give an example of an input device for the sat nav for a disabled person and explain how it is useful.
-Keyboard. Only sensible one so far.
Why does the satnav need a secondary storage device?
-store maps, previous locations etc.
Why solid state storage?
-Portable-small, light
-withstand movement, no moving parts
Why are the commands stored as binary?
-1 and 0 can easily be represented via on and off siganls. It allows easy simple logic gates. It allows less error as there are only two values
Name a task carried out by the CPU:
-To fetch/execute commands from memory
-To decode commands
-To carry out the fetch, decode, execute cycle
-Perform Logic operations

Question 2: HTML and internet
What else might be in an HTML file other than text for the webpage?
-image references
-cascading style sheets, CSS
-video references
One reason why is it good for HTML to be a standard?
-All webpages are the same (pretty much) so browsers only have to support html
-People can have gaurenteed support for their webpage
-Other languages can be implemented effectively such as php, javascript and xml
Hex
- 58 = 3A, 156 = 9C
Another question ??

How does the DNS connect the user to a webpage from the URL?
The DNS has access to a database and associates the URL with a specific IP address. This can access the files and connect the user to the IP which also allows the DNS to contact the correct website.

3: Algorithm (I think)
Fill in the gaps
-'count' and 'Total / Quantity)
What is a constant and give an example?
-A value stored in a specific memory location represented by a name. The value cannot be changed while the program is running
E.g. Quantity
What data type is the Mean?
Real as it could be a decimal.
What other two types of iteration are there other than For?
-while
-repeat/do until ?
It gives an example of a validation algorithm, Give an example of a boundary value and an invalid value.
-100 or 0 are boundaries
-anything not between 0 and 100 inclusive are invalid values

4: Databases
Why is a database a persistent organised store of data?
-It is a structured object that contains data. It is stored in tables. (Not sure about this one)
What is a suitable data type for the ID?
Text, as it has leading zeros
How many records are there
-four
Which field is the primary key?
-The first field, it is unique and follows the same format. It is a short number.
Name a validation method for TeacherID and Date, they must be different.
-TeacherID, follow format Letter,Letter,ID, or must be length three etc
-Date, follow format DD/MM/YYYY or it must be less than or equal to the current date
Name two features of a DBMS that allow you to make customizable applications.
-Query, ask for records with certain attributes easily, e.g this lets the admin create a query for all outstanding repairs
-Form, create a GUI to make it easier to make a query, e.g. admin enters teachers ID into search box to get their repairs.

Question 5: Cars
Describe the ethical and legal issues surrounding the development of automatic technology such as driverless cars.
-Cars follow the law always and may not cope in an emergency situation and therefore ccause harm.
-Cars and automatic devices collect data perhaps unethically or illegally
-Automation increases unemployment, not right for robots to 'take over'
-Security required and so could break the data protection Act
-Hackability, could break the computers misuse act
Question 6: OCR accounts
Two advantages of a network in the office over standalone PCs:
-Share expensive peripherals. All users can use the peripherals plugged in to any PC. This saves money as only one peripheral is needed and all the computers have access saving time.
-Share data/resources/programs. This allows quicker sharing of data and ideas over methods such as email. It is cheaper as users do not have to use physical storage devices to transfer data. Saves time as users do not have to take so long copying files as they are in a shared folder.
Name a piece of hardware to get an internet connection. Usually OCR accepts:
Router, modem (modulator-demodulator) or ADSL adapter
Name two other pieces of hardware for a network and explain:
-Router/modem/ADSL, internet connection
-Hub, connect the devices for sharing
-NIC, allows connection via Ethernet or wireless
-Server, dedicated machine to supply data to clients etc.
-switches, like a hub but faster
Network policies:
-Acceptable Use: User priviliges, malware protection etc
-Backup
-Failover
-Disaster Recovery
-Archive

Pseudocode:
the criteria were
Use iteration
Have a previously stored number to guess
allow ten guesses
say to guess higher or lower
ask the user to guess
say congratulations and end the game if they guess it

I guess that it is one mark per criteria

approximately
Const Value = random number
count = 0
Ouput 'Guess the number'
Repeat
Output 'enter a number'
Guess = Input
If Guess = Value Then
Output 'Congratulations'
END
If Guess > Value THEN
Output 'guess higher'
if guess < Value then
Output 'Guess lower'
count = count + 1
Repeat until count = 10
output 'Sorry you did not guess the number. It was' + value
END
Thanks for all the input people have given

If anyone else has question answers contribute to help update the full markscheme


First question requires you to say hardware and software work together to create a functional, coded output

Secondary storage question wasn't directly linked to satnavs, it just asked why secondary storage is used so you define it

DBMS question could've had Reports and aren't forms ways of inputting data? Reports are the ones that create a snapshot of data in a given time

For hardware in networks I think cables are valid because without cables there would be no infrastructure to the network, yes they can have dedicated wifi connections but wifi connections do not connect to a centralised server

I thought the HTML question asked you to define HTML? Ah, two marks lost

Also, the second one came up in an exam prior. MS answer was something along the lines of "Web browsers have to interpret the text file to be able to display it, if HTML is an accepted standard then web browsers will conform to this standard and display the contents of the text file correctly" Or something

For the DNS question, to get the third mark you need to say that the database is updated by DNS servers regularly

For the databases one, the database is persistent and thus it must be none volatile idk

Also, I think your algorithm was incorrect
(edited 6 years ago)
What would 50/80 be?
Original post by BenKennedy55
QUESTION 1
1a) What is a computer system?
Hardware and software working together to form a coded solution
1b) Why is an input device needed?
To input the data needed for processing and outputting
1c) Example of input device for satnav and explanation
Microphone: For users who are disabled in their hands (Other suitable explanation)
1d) Why does a satnav need secondary storage?
Because when the satnav is turned off the RAM is also turned off, RAM is volatile and the satnav needs somewhere to store that memory e.g. Favourite locations,recent destinations
1e) Why is solid state suitable for a satnav?
Solid state is used because there are no moving parts which is efficient in a car as a car is moving so the data doesn't get damaged/corrupt
1f) What is ONE purpose of a CPU?
To fetch data from memory/ execute instructions/ decode data fetched from memory
I believe there was another part to question 1, I hope this is okay :biggrin:

QUESTION 2
2a) What else would be included in the HTML file except text?
Hexadecimal numbers to code for a specific colour? (Was unsure of this)
2b) Describe the benefit of using HTML as a standard?
Most (if not all) web browsers can read and display HTML (Again, not sure)
2c) Hexadecimal numbers
3A and 9C

I'll post the rest of my answers later, I have a technology paper to revise for :frown:


When do you plan on finishing this?
Original post by Manlikeytu
What would 50/80 be?


A/A* depending on whether GB go down or up :smile:
Original post by honestlykms
A/A* depending on whether GB go down or up :smile:


So atleast an A? Because thats what I need to get an A star overall
That went pretty well, apart from one slight oversight on my part - when giving an example of invalid data, I put 'potato'. Legit. I have absolutely no clue whether I've completely messed up or if I'm actually right, since 'potato' is a string value, and only integers would be used, which makes it invalid..?
Original post by Manlikeytu
So atleast an A? Because thats what I need to get an A star overall


Probably, don't take my word but I think it's really unlikely that you'll get a B
Original post by zainrazaa
That went pretty well, apart from one slight oversight on my part - when giving an example of invalid data, I put 'potato'. Legit. I have absolutely no clue whether I've completely messed up or if I'm actually right, since 'potato' is a string value, and only integers would be used, which makes it invalid..?

I am pretty sure the examiner will give you the mark for making him/her laugh:biggrin:
Original post by The RAR
I am pretty sure the examiner will give you the mark for making him/her laugh:biggrin:


yessshh i got dis
Original post by zainrazaa
yessshh i got dis


i did the same

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