todo

Question 1

Names of logic gates

Answer 1

1. AND gate
2. NOT gate
3. OR gate
4. NOR gate
5. NAND gate
6. XOR gate

Question 2

Binary to denary

Answer 2

Add numbers (1,2,4) that have a 1 below them

Question 3

Denary to binary

Answer 3

Does 256 fit into _?, Does 128 fit into _? If yes put a 1

Question 4

Binary to hex

Answer 4

Split number into groups of 4 and add the ones

Question 5

Hex to binary

Answer 5

Convert letters to numbers. Convert each number into binary using base 2

Question 6

Hex to denary

Answer 6

Multiply each digit by its value on base 16 and add the results together.

Question 7

Denary to hex

Answer 7

Divide each number by 16 and then read the remainder from bottom to top. (convert into letters if needed)

Question 8

Uses of the hexadecimal number system

Answer 8

• HTML and CSS colour codes
• MAC addresses
• Assembly code
• Memory dumps
• Web addresses

Question 9

Uses of binary system

Answer 9

• Computer registers
• Robotics
• Counting systems
• Digital instruments

Question 10

Why might programmers prefer to read in hexadecimal rather than in binary?

Answer 10

It is easier to fiend errors, binary consists of zeros and ones, hexadecimal takes up less visual space

Question 11

What does the symbol “terminator” do and how does it look?

Answer 11

It indicates the START/END of a system. It looks like a rectangle with soft edges.

Question 12

What does the symbol “input/output” do and how does it look?

Answer 12

It indicates when INPUT is required from the user if OUTPUT is being sent to the user. It is a parallelogram

Question 13

What does the symbol “process” do and how does it look?

Answer 13

It names a process within the system. It. is a rectangle.

Question 14

What does the symbol “data flow line” do and how does it look?

Answer 14

It joins to operations, the arrowhead indicating the direction of the flow. It is an arrow.

Question 15

What does the symbol “decision” do and how does it look?

Answer 15

It is a point in the sequence where alternative paths can be taken, yes or no. It is a rhombus.

Question 16

What is a string?

Answer 16

A string is text, it treats all data as text.

Question 17

What is an integer?

Answer 17

An integer is a whole number, you can perform calculations with these.

Question 18

What is a variable?

Answer 18

A variable is a piece of data that you can alter that has also been given a name.

Question 19

What is a constant?

Answer 19

A named memory location that contains data that can be read but not changed by the program

Question 20

What is a real?

Answer 20

Positive or negative fractional values. (“float”)

Question 21

What is a char?

Answer 21

A single character or symbol. (“str”)

Question 22

What is a boolean?

Answer 22

One of 2 values, true or false (“bool”)

Question 23

Global variables

Answer 23

Variables that can be accessed from any routine in the program

Question 24

Local variables

Answer 24

Variables that can only be accessed in the code element in which they are declared

Question 25

How do you write to the power of something in python?

Answer 25

**

Question 26

How do you write square root of something in python?

Answer 26

**0.5. or math.sqrt

Question 27

What is sequence?

Answer 27

Sequence is the order in which the instructions are executed.Sequence is the first programming construct.

Question 28

What is selection?

Answer 28

Selection is the second programming construct. Selection is the process of making a decision. The result of the decision decides which path the program will take next.selection is implemented using IF THEN or IF THEN ELSE statements:

Question 29

What is iteration?

Answer 29

Iteration is the third programming construct. There are times when a program needs to repeat certain steps until told otherwise, or until a condition has been met. This process is known as iteration

Question 30

What is a subroutine?

Answer 30

A sequence id program code that performs a specific task but does not represent the entire system. All subroutines in python need a name and def which is short for define.

Question 31

What are the advantages of using subroutines?

Answer 31

• It can be called when needed. This improves the modularity of the code, makes it easier to understand and helps in the identification of errors.
• There is only one section of code to debug.
• There is only one section of code to update

Question 32

Types of subroutines

Answer 32

-Procedures: Small sections of code that can be reused, they do not return a value. In pseudocode: Procedure/Endprocedure. They are called by using the CALL statement.
-Functions: They have one or more values passed to them and one or more values are returned to the main program after they have completed running. In pseudocode: FUNCTION(values to be passed in)/ENDFUNCTION
The CALL statement is used to execute the function but the values required must be passed to the function at the same time:
CALLmy_function(values required by the function)