The Sutton Academy - Home · Web viewA CPU can be RISC or CISC. Describe the difference between a...
Transcript of The Sutton Academy - Home · Web viewA CPU can be RISC or CISC. Describe the difference between a...
Computer Science Component 1Understanding Computer ScienceNovember 2017 releaseIn the style of EduqasTime 1 hour 45 mins
Marks Available 100
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1. Memory is an important component in a computer.
Tick () the correct boxes below to show whether the statements apply to RAM or ROM. [3]
STATEMENT RAM ROM
Contains instructions and data for the programs
that are running.
Non -volatile
Stores programs and data to boot up the computer
2. The Central Processing Unit or CPU is an important computer part.
(a) Describe the role of the CPU in a computer. [2]
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(b) CPU’s have registers such as the Current Instruction Register and the Memory Address
register. Describe what a register is. [2]
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(c) A CPU can be RISC or CISC. Describe the difference between a RISC processor and a CISC
processor and explain where might they be used. [5]
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(d) A CPU has 6MB of cache memory. Describe the function of cache memory. [2]
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(e) Sometimes a computer might need to use virtual memory. Describe how virtual memory
works. [2]
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3. A 6th form student is going to buy a laptop to help with her studies. She has the choice of buying
one with a Solid-State Drive or a Hard Disk Drive. Discuss the suitability of both types of storage
technology for a laptop. [6]
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4. The TCP/IP protocol, on which the Internet is built, is modelled using the TCP/IP 5-layer model.
Complete the table which summarises the 5-layer model. [6]
Order in
the Model
(5 - top of
the model)
LayerProtocol /
connectionDescription
1 EthernetAllows data to be transmitted and
received.
Network Layer IP
Application LayerThe group of applications requiring
network communications.
2 Data Link Layer MAC Where the network hardware operates.
4 TCP/UDPEstablishes connection with remote host.
Divides data into packets.
5. A common way for database security to be breached is through SQL injection.
(a)
(i) Explain how SQL injection works. [2]
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(ii) How can an organisation protect itself from SQL injection? [2]
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(b) Describe one way an organisation could identify security vulnerabilities in its systems. [2]
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6.
(a) Showing your workings complete the table below, converting between denary, binary and
hexadecimal numbers as necessary. [6]
Hexadecimal Denary Binary
D416 21210 110101002
19510 110000112
1316 000100112
9E16 15810
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(b)
(i) Showing your workings, add 001110112 010101012 [2]
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(ii) Using an example of binary addition, explain the concept of overflow. [4]
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(c) Using an example demonstrate and state what effect an arithmetic shift of one place to the
right has on a byte. Then demonstrate and state what effect an arithmetic shift of two
places to the right will have on the same byte. [4]
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7. Many computers make use of utility software. Using an example of a type of utility software,
describe what utility software is and the particular function of your example. [3]
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8. The diagram below shows a representation of a bitmap image.
LBL DB G G B LBL
B G G DG G LBL
DG G DG DG G DG
B B BR LB B B
B B DB BR B B
DG G LB DB DG G
The colours are as follows
G Green
SB Sky Blue
LBL Light Blue
DG Dark Green
BR Brown
DB Dark Brown
B Blue
LB Light Brown
(a) Explain using the example how this image would be stored on a computer. [3]
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(b) State two pieces of metadata stored in image files. [2]
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(c) The image can be compressed. Discuss the difference between lossy compression and
lossless compression. [2]
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State how reducing the amount of colours in the image would have an effect on the quality and
file size of the image. [2]
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(d) An image is compressed from 360 kb to 120kb. Calculate the compression ratio. [2]
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9.
The diagram shows a computer network.
(a) What are the following components? [3]
A ……………………………………………………………………………………………….
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C………………………………………………………………………………………………..
(b) A small business is thinking of changing its network from a client-server network to a peer-
to-peer network. What are the benefits and drawbacks of a peer-to-peer network
compared with a client server network? [6]
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A B
C
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10. Boolean logic reflects the way the logic gates work in a computer’s CPU.
(a)
(i) Complete the following truth table. [3]
(ii) Use this truth table to simplify the expression [1]
A+A . B
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A B A A .B A+A . B
1 1
1 0
0 1
0 0
(b) Using the following identities:
simplify the Boolean expression: [3]
X=(A+B ) . A
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P .P=0
(P+Q ) .R=(P .R )+(Q .R)
P+0=P
(c) The following diagram shows a logic system.
Write down the Boolean expressions for each of the outputs Q1, Q2 and Q3 in terms of the
inputs A, B and C
Q1 = ...................................................... [1]
Q2 = ...................................................... [2]
Q3 = ...................................................... [1]
11. Programs can be written in High Level Language or Low-Level Language.
(a) Discuss the difference between a High-Level Language and a Low-Level language. [4]
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(b) Describe the situations where a Low-Level Language might be used. [2]
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12.
(a) Smartphones are often only used for two years. Identify two reasons for this. [2]
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(b) A student is thinking of replacing his computer monitor with a more energy efficient version.
Discuss the environmental impact of this. [6]
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(c) Identify how expansion of the internet access has a negative effect on the environment.
[2]
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