Paper 1 Flashcards
Identify one reason why programmers use hexadecimal notation.
Easier for humans to read
Identify the number of binary patterns that can be represented by 8 bit
(2 to the power of 8)
256 values
Give the number of bits per character used by standard ASCII.
7
State what is meant by the term pixel.
The smallest block of colour in an image
[…]16 different colours.
State the minimum number of bits that would be needed to represent
one pixel.
4
Give one reason for connecting computers in a local area network.
communicate (e.g. email)
State the purpose of network protocols.
enable
communication
between devices
Identify the layer of the TCP/IP model that would add the File Transfer Protocol (FTP)
Application
Give one task carried out by the network layer
Adds the source/destination IP address to each packet so that they can reach their designated destination
Benefit of Bus topology
The length of cable required is less than star topology
Disadvantage of bus topology
If the main cable/a terminator fails or gets
damaged the whole network will fail
Give two reasons why lossy compression is used when distributing music files over the internet
Reduces time taken to upload/download
People have a limited hearing range / can’t
tell the difference
Identify a file format that uses lossy compression
JPEG
why must a computer have hardware and software
The software “tells” the hardware which tasks to perform, and hardware makes it possible to actually perform them
Give two reasons, other than cost and capacity, why Zakir may choose a solid state drive rather than a hard disc drive
- Less heat generated
- Silent operation
- Longer battery life
Explain one difference between flash memory and RAM
Flash memory is non-volatile (1) whereas RAM is
volatile
Explain the purpose of cache memory
cache is a temporary storage
and is used to speed up processing
types of anti-malware software
- Antivirus (1)
- Anti-spyware (1)
- firewall
Give one reason, other than cost, why scientists use simulations.
Predict/model outcomes
Explain one reason why a simulation may require a powerful processor.
- Simulations (may) use/collect large amounts of
data (1) - Simulations (may) involve a large number of
calculations (1)
Describe the stored program concept
Instructions are stored in memory (1)
* Instructions (and data) are fetched, decoded, and
executed (1)
types of registers
- Program counter / PC
- Memory address / MAR
- Accumulator/ACC
Describe the role of the address bus and the data bus during the fetch part of the cycle.
Address of instruction carried on address bus to main memory. Contents at that address carried back to the CPU on the data bus
Effect of Increasing the width of the
data bus
Increases the number of data
Effect of Increasing the width of the address bus
Increases the number of memory locations that can be directly addressed
Explain why the variable Temp is needed
You need to swap the contents of array values (1) and without
Temp one of the values would be lost (1)
two advantages of choosing a programming language that uses a compiler,rather than an interpreter, for a program that will be distributed on a DVD.
Compiled code is smaller than the original code (1),
which may not fit on the DVD
Explain one difference between DNA computing and traditional computing
DNA uses chemical reactions (1) rather than
electrical properties (1)
Give a definition of the term superposition in quantum computing.
Multiple probabilities at the same time
Ethically, everyone should be able to access the benefits of technology.
Give two reasons why this may not be possible.
- Some people may not want to use technology
- Some people may not be able to afford to use
technology
(PART ONE )Discuss the negative environmental impact of using computers and actions that
could be taken to reduce it.
- needs lots of water for manufacturing
- Some countries require sellers to recycle own waste
(PART TWO)Discuss the negative environmental impact of using computers and actions that
could be taken to reduce it.
- Computing devices sent to landfills contaminate ground and water
- Find charities which take donations of old devices
(PART THREE)Discuss the negative environmental impact of using computers and actions that
could be taken to reduce it.
- Alot of energy used to keep machines cool with air conditioning or fans
- Turn off machines when not in use
analougue to digitaL
- set the sample rate
- sample the analogue sound
- measure the sound amplitude
internal and external differences
HDDs or SSDs :
- large amounts of data
- portable
- moving parts
USB sticks SD cards:
- smaller
- reasonably large amounts of data
exernal
HDDs or SSDs
large amounts of data
portable
moving parts
USB sticks SD cards (smaller/reasonable large amounts of data)
wireless advantages
convinient - move around while connected
cheaper
easy to add more users
wireless dissadvantages
- generaly less secure (access point available to all devices so hackers can gain access)
- less reliable
