Computer Science for IGCSE & O level - Data Representation (Section 11)
1
Which statements are accurate regarding MAC addresses?
2
What is the primary benefit of using a high color depth (e.g., 24-bit) in digital images?
Répondre(B)
It enables a wider range of colors to be displayed.
3
Which of the following best explains why hexadecimal is useful in computer science?
Répondre(A)
It makes data easier for humans to read and understand.
4
What is a benefit of using the hexadecimal system to represent binary data?
5
What is a crucial aspect of the MP3 audio format?
Répondre(C)
It is a lossy compression format.
6
In computer graphics, what does the term 'pixel' represent?
Répondre(A)
The smallest addressable element of an image.
7
What happens to the sign of a number when performing an arithmetic right shift on a negative number?
8
What are the aims of data compression?
9
What is 'color depth' in digital images measured in?
10
What are the downsides of lossy compression compared to lossless?
11
How many possible combinations of colours can be represented with HTML color codes using the hex format?
12
What does a sampling resolution refer to?
Répondre(B)
The number of bits used to represent each sample.
13
What does each cell or square represent within a bitmap image?
14
What is the hexadecimal equivalent of the decimal number 100?
15
Which is the main trade-off when using lossy compression?
Répondre(B)
Lower file size versus potential data loss.
16
In HTML, what do color codes represent?
Répondre(D)
The colour of the web page elements.
17
What is the purpose of using two's complement in binary representation?
Répondre(B)
To represent negative numbers.
18
In two's complement, what is the equivalent of inverting the bits and adding 1?
Répondre(B)
Finding the two's complement
19
Which of the following is NOT a key number system used in computer science?
20
Which statements are true regarding lossy data compression?
21
What does 'resolution' refer to in the context of a digital image?
Répondre(C)
The number of pixels used to represent the image.
22
Which factors influence the final size of a compressed file?
23
What are the common uses of RLE (Run Length Encoding)?
Répondre(A)
To compress data with long runs of repeated characters.
24
What does the term bit depth refer to in the context of digital audio?
Répondre(B)
The number of bits used to represent the amplitude of each sample.
25
Which of the following is a disadvantage of lossy compression?
26
In the context of bitmap images, what does 'color depth' refer to?
Répondre(B)
The number of distinct colors each pixel can represent.
27
What is the most significant advantage of Lossy compression?
28
Which factor(s) will increase the file size of a bitmap image?
29
Which of the following is the binary representation of -2 in 4-bit two's complement?
30
Which of the following best describes the purpose of Run Length Encoding (RLE)?
Répondre(C)
To reduce the size of data by replacing repeating characters.
31
What is the equivalent decimal value of the hexadecimal number '10'?
32
Which of the following components determines the resolution of the sound?
33
What is the correct way to convert +6 to a two's complement representation with 4 bits?
34
What's the primary goal of using compression algorithms like JPEG?
Répondre(C)
To decrease the file size.
35
Which file format is most commonly associated with Lossy compression?
36
What is the maximum decimal value that can be represented by an 8-bit two's complement integer?
37
What are the two numbers represented by binary digits?
38
What is the main advantage of using the two's complement format for representing integers?
Répondre(A)
It simplifies the addition and subtraction of both positive and negative numbers.
39
What is the largest decimal number that can be represented with a 8-bit binary number?
40
What type of values can be represented using hexadecimal?
41
What is sampling rate, and how does it relate to sound quality?
Répondre(A)
The number of samples per second. A higher rate means better sound quality.
42
If an image is 1920 pixels wide and 1080 pixels high and has a color depth of 8 bits (256 colors), what is its uncompressed size in bytes?
43
Which type of compression is used in a ZIP file?
44
What are the key aspects of lossless compression?
Répondre(A)
The original data can be perfectly reconstructed.
45
What are the main factors that affect the size of a video file?
46
Which is the equivalent of the hexadecimal value '11' in decimal?
47
Which factors influence the size of a digital image?
48
If a sound file is sampled at a higher sample rate, what is the likely effect on the file size?
Répondre(B)
The file size will increase.
49
How can the operation of 1100 + 0110 be validated in decimal?
50
What is the result of shifting the binary number 10101010 one position to the right?
