2.1 - Data Representation

Question 1

What is Bit short for?

Answer 1

Binary Digit

Question 2

How many numbers can be represented by a Bit? What are they?

Answer 2

2 Numbers.

They can be a 0 or a 1.

Question 3

What is the smallest unit of storage?

Answer 3

Bit

Question 4

What is a collection of 8 bits known as?

Answer 4

Byte

Question 5

Order these from smallest to largest.

TB, KB, GB, Byte, MB, Bit

Answer 5

Bit, Byte, KB, MB, GB, TB

Question 6

How many bytes are in a KB?

Answer 6

1024 Bytes

Question 7

How many GB are in a TB?

Answer 7

1024 GB

Question 8

How many bits are in a byte?

Answer 8

8 Bits

Question 9

How many MB are in a GB?

Answer 9

1024 MB

Question 10

How many KB are in an MB?

Answer 10

1024 KB

Question 11

How much storage space would be required to store a characters in a text file (e.g. T, +, 7)

Answer 11

1 Byte

Question 12

How much storage would be required to store the word “Computer” in a text file?

Answer 12

8 Bytes (One for each character)

Question 13

How much storage would be required to store a 64 x 64 pixel jpeg file?

Answer 13

12 KB

Question 14

How much storage would be required to store a 10-megapixel photo?

Answer 14

11 MB

Question 15

How much storage would be required to store a five minute MP3 audio file?

Answer 15

5 MB

Question 16

How much storage would be required to store one hour of video data?

Answer 16

2 GB

Question 17

Is KB and Kb the same unit of measurement?

Answer 17

No.

KB stands for Kilobytes

Kb stands for Kilobits

Question 18

To calculate the range of values for n bits we have to use which formula?

Answer 18

0 - (2n - 1)

Question 19

If you were to write an 8 bit binary number. What is the left most bit known as?

Answer 19

Most Significant Bit (MSB)

Question 20

If you were to write an 8 bit binary number. What is the right most bit known as?

Answer 20

Least Significant Bit (LSB)

Question 21

If you are converting a denary number into its binary form, what are the headings you would use?

Answer 21

128 64 32 16 8 4 2 1

Question 22

After you have worked out a binary value for a denary number what should you always do to ensure your answer is correct?

Answer 22

Add up all of the headings with a 1 underneath them to ensure that you have got the correct answer.

Question 23

Why do we need to use a Two’s Complement System?

Answer 23

To allow for negative numbers to be shown

Question 24

In Two’s Complement, the MSB becomes a _____________, to tell us if the number is either positive or negative.

If the number is positive you will see a _____ at the beginning of the binary number.

If the number is negative you will see a _____ at the beginning of the binary number.

Answer 24

1. Sign Bit
2. 0
3. 1

Question 25

What is the range of values for typical binary numbers?

Answer 25

0 - 255

Question 26

What is the formula we use if we are finding Two’s Complement numbers?

Answer 26

(-2n - 1) to (2n-1 - 1)

Question 27

When working out Two’s Complement numbers we have to go through 3 steps.

What is missing from each step?

Step 1: Convert 71 into ___________

Step 2: _________ the bits. Change 0’s to 1’s and 1’s to 0’s.

Step 3: Add ____

Answer 27

1. Binary
2. Flip
3. 1

Question 28

What is a character set?

Answer 28

1. Set of symbols that may be represented in a computer at a particular time
2. Symbols called characters can be classified as letters, numbers and punctuation marks.
3. Each character has a unique binary code.
4. These include displayable characters, letters, numbers and punctuation marks.
5. Also contains “control” characters: Non-printing and used for special purposes e.g. end of file marker.
6. Two examples include ASCII and Unicode