A small revision booklet with questions for students to complete over the easter holidays

1. Computer Science
Easter homework
DUE the first lesson back after the break!!!!!
Programming practice
To become familiar with the programming language
Complete the practice python programming tasks on code academy
http://www.codecademy.com/learn
A great book to learn to program:
http://files.swaroopch.com/python/byte_of_python.pdf
If you have any difficulties please feel free to contact:
p.morris@montomeryschool.co.uk
l.harwood@montgomeryschool.co.uk
Richard.west@go.edgehill.ac.uk
As well as using Montgomery high school on google + or @montyict on twitter
Theory Revision

2. Data Types
Boolean True /false
String It is hot outside
Integer 457
Floating Point 3.548
What data type is counter?
Please define the following
Variable
Iteration
Algorithm
Syntax error

3. Network Topology
Network topology refers to how computers are connected to a
network. There are three main types of network topology: bus, ring
and star.
The bus network
In a bus network all the workstations, servers and printers are joined
to one cable (the bus). At each end of the cable a terminator is
fitted to stop signals reflecting back down the bus.
The ring network
In a ring network each device (workstation, server, printer) is
connected to two other devices, this forms a ring for the signals to
travel around. Each packet of data on the network travels in one
direction and each device receives each packet in turn until the
destination device receives it.
The star network
In a star network each device on the network has its own cable that
connects to a switch or hub. A hub sends every packet of data to
every device, whereas a switch only sends a packet of data to the
destination device.
Pick one of the topologies and research their advantage and
disadvantages as well providing a drawing of a typical layout.

4. DECIMAL BINARY CORRECT?
0 8 4 2 1
1 8 4 2 1
2 8 4 2 1
3 8 4 2 1
4 8 4 2 1
5 8 4 2 1
0 1 0 1
Example
6 8 4 2 1
7 8 4 2 1
8 8 4 2 1
9 8 4 2 1
10 8 4 2 1
Binary Numbers
Binary means two. All
numbers in binary are
made up of either a 0 or a
1.
To work out a decimal
number we use a grid like
the ones on a left.
Decimal number 5
Is there any eights in five?
NO! so a zero goes in the
eight column.
Are there any fours in 5.
Yes so we put a 1 in the
four column.
Leaving one!
So we out the one in the 1
column and not the two
column
Now work out the binary
numbers for the other
questions.

5. Flowchart
Create a flowchart which demonstrates the process of ordering a
meal at a fast food restaurant.

6. Database / SQL
Table = Menu
Meal-code Name Price Meal-deal
1001 Fish Fingers 1.99 No
1002 Hot Dogs 2.85 No
1003 Turkey Burgers 2.19 No
1004 Jacket Potato 2.50 Yes
1005 Chicken Korma 3.25 No
Which of the above would be the primary key?
The following SQL statement has been executed to the database table
above what would happen?
SELECT Name, Price, Meal-deal
FROM Menu;
Where Meal-code = 1004;

7. Data Structures (revision only)
The study of data structures is about organising data so that it is suitable
for computer processing. Computer hardware looks at storage devices
like internal memory and disks as holders of elementary data units
(bytes), each accessible through its address (usually an integer).
Defining data structures
A data structure can be defined as a collection of different data
elements, which are stored together in a clear, structured form.
In programming, one of the most important design decisions involves
choosing which data structure to use. Arrays and linked lists are among
the most common data structures and each is applicable in different
situations.
Data structures: arrays
There are situations during the writing of code when programmers need
to hold related data as a single item, for example a list of employees’
names or makes of car. One method of doing this would be to assign a
variable to each item in the list.
One-dimensional arrays
A one-dimensional array in Python and PHP is a data structure that
allows a list of items to be stored with the capability of accessing each
item by pointing to its location within the array.
0 1 2 3
0 A B C D
1 E F G H
2 I J K L
3 M N O P

8. The reason why this type of array is referred to as a
‘one-dimensional array’ is that it only uses a single
number to point to the position of array elements.
Two-dimensional arrays
Two-dimensional arrays are a little more complex than the one-
dimensional versions, but really they are nothing more than an array of
arrays, in other words an array in one row and another in the next row.
4 Q R S T

9. Hardware
Hardware is a name given to a collection of physical ‘things’ that when
put together in a certain way form a ‘system’.
Computer hardware: system unit
Within a computer system there are basically two types of hardware. The
hardware within the system consisting of the CPU (central processing
unit), which is situated on a printed circuit board called the motherboard.
There is the hard disk drive, the RAM (random access memory), optical
drive and other circuit boards such as the graphics and sound cards.
These are all regarded as hardware because if you removed the case you
could physically touch the devices – although you should not do this
unless you know what you are doing.
Describe what the purpose of CPU & RAM along with
typical specs and costs each.
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