Computer Science for IGCSE & O level - Data Representation (Section 17)
1
What is the purpose of logical binary shifts?
Απάντηση(C)
To multiply or divide a binary number by a power of 2.
2
What could the error code "00000010" potentially indicate?
3
What is the hexadecimal value for the colour black?
4
Which HTML color code represents the color black?
5
What is the maximum number of different values that can be represented by 4 bits?
6
If a binary number is shifted four places to the left, what is the equivalent arithmetic operation?
7
In the binary system, which two digits are used to represent all values?
8
Which of the following is a trade-off typically involved when using Lossy compression techniques?
Απάντηση(B)
Loss of data in exchange for smaller file size.
9
When converting from hexadecimal to decimal, which process must be followed?
10
Which statement describes the main trade-off when choosing between lossy and lossless compression techniques?
Απάντηση(C)
Lossy compression offers higher compression ratios but may reduce quality.
11
If an audio file is converted from 16-bit to 8-bit resolution, what effect does it have on the file size?
12
In HTML color codes, the values are represented using a 6-digit hexadecimal code. What do these pairs of digits represent?
Απάντηση(A)
The amount of red, green, and blue.
13
How many different colors can be represented using a 16-bit color system (without accounting for alpha)?
14
What is the purpose of the leftmost bit in a two's complement representation of a number?
Απάντηση(B)
Represents the sign of the number.
15
Which of the following statements are true regarding the binary number system? (Select all that apply)
16
Which hexadecimal code represents the color yellow?
17
What is the primary goal of image and video compression?
18
What aspect of an image is most impacted by increasing its resolution?
19
If the image is 2048 pixels wide by 1536 pixels high, and it's a 16-bit color depth. Approximately how many MB is the uncompressed image?
20
What are some examples of things represented using hexadecimal notation?
21
What happens during a lossless data compression process?
22
What does the abbreviation 'MAC' stand for in the context of networking?
23
In a 24-bit color image, how many possible colors can a single pixel represent?
24
What is the hexadecimal equivalent of decimal 12?
25
Which method is often used when compressing text files to make them smaller?
26
What is the primary advantage of Unicode over ASCII?
Απάντηση(B)
Unicode can represent characters from all languages.
27
Which of the following statements is true about two's complement?
Απάντηση(C)
It is used to represent both positive and negative integers.
28
Which of the following is a common application of hexadecimal numbers?
Απάντηση(B)
Representing colors in HTML.
29
What operation is performed when you shift a binary number by three places to the right?
30
What is the result of 10110101 shifted right by two places?
31
What happens to the number 1100 in binary if you shift it one place to the left?
32
What is the main characteristic of an analog signal?
Απάντηση(C)
It is continuous in time and amplitude.
33
How many ASCII characters are there?
34
What is the effect on file size if an image's resolution is increased while keeping the color depth constant?
35
Which of the following best describes the purpose of a MAC address?
Απάντηση(B)
To uniquely identify a device on a local network.
36
In a right logical shift of a binary number, what happens to the bits?
Απάντηση(B)
Bits are shifted to the right.
37
What is the result of converting the 8-bit binary number 10110011 to its decimal equivalent using the two's complement method?
38
What determines the number of colours that can be represented in an image?
39
Which of the following terms represents the largest unit of memory?
40
What does the acronym 'JPEG' stand for, in terms of image file formats?
Απάντηση(A)
Joint Photographic Experts Group
41
What is the result of adding the binary numbers 111 and 101?
42
Which hexadecimal color code represents white?
43
What are the 2 main components used in the digital representation of sound?
44
In HTML, how are hexadecimal values generally denoted?
45
Which of the following factors typically has the MOST significant effect on the size of a video file?
Απάντηση(B)
The compression codec used.
46
What is the largest decimal number representable by a 4-bit unsigned integer?
47
Which of the following file formats are generally associated with lossy compression?
48
What determines the amount of data required to represent an audio file?
49
What is the difference between the ASCII and Extended ASCII character sets?
Απάντηση(C)
Extended ASCII includes characters not in the original ASCII set.
50
What is the term for the process of reducing the file size of an image or sound file?
