Computer Science for IGCSE & O level - Data Representation (Section 18)
1
What is the meaning of the term 'sampling rate' in sound recording?
Răspuns
(A)
The number of times the sound is measured per second.
2
If a binary number is shifted three places to the left, what is the equivalent arithmetic operation performed?
Răspuns
(B)
Multiplying by 8
3
What is the relationship between the sampling rate and the size of a digital audio file?
Răspuns
(C)
A higher sampling rate generally results in a larger file size.
4
Which of the following are advantages of file compression?
Răspuns
A
B
5
What is the equivalent decimal value of the hexadecimal number '1A'?
Răspuns
(C)
32
6
Which of these is a key characteristic of the hexadecimal number system?
Răspuns
(C)
Uses sixteen symbols.
7
Which options accurately describe the characteristics of lossless compression?
Răspuns
A
B
D
8
If the bit depth of an image is increased from 8 bits to 16 bits, what is the effect on the file size?
Răspuns
(B)
The file size is doubled.
9
Which color does the HTML code #008000 represent?
Răspuns
(B)
Green
10
What is the maximum value represented by a single hexadecimal digit?
Răspuns
(C)
15
11
In HTML, what is the purpose of the hexadecimal color code?
Răspuns
(D)
To represent different colors used in the web page.
12
The image of a black and white image consists of 64 squares. If each square requires 1 byte of storage, and RLE is applied. What would be the storage requirement for a full black image?
Răspuns
(B)
2 bytes
13
Which of the following are advantages of data compression?
Răspuns
A
B
C
14
What does the term 'unsigned integer' mean in computer science?
Răspuns
(B)
An integer that can only represent positive numbers.
15
A bit is the basic unit of all computing memory storage terms and is either 1 or 0. The word comes from binary digit. The byte is the smallest unit of memory in a computer. 1 byte is 8 bits. A bit is sometimes called a nibble - half a byte. What is the relationship between byte and bit?
Răspuns
(C)
1 byte = 8 bits
16
What does the term 'bit' refer to?
Răspuns
(B)
A binary digit
17
If a bitmap image has a color depth of 8 bits, how many different colors can each pixel represent?
Răspuns
(D)
256
18
What does a higher sampling rate result in for digital audio?
Răspuns
(B)
Higher sound quality and a larger file size.
19
In run-length encoding (RLE), what is the purpose of representing consecutive identical data values?
Răspuns
(C)
To reduce the file size.
20
What are the 2 ways in the image that allow to find a negative binary representation?
Răspuns
C
D
21
What is the main function of the ASCII control characters?
Răspuns
(B)
Manage text formatting and communication
22
What is the purpose of using compression algorithms like JPEG for images?
Răspuns
(B)
To decrease the file size while maintaining a reasonable image quality.
23
What will happen if the binary number 1111 is shifted one place to the left?
Răspuns
(A)
Multiplied by 2
24
What are the key principles of run-length encoding (RLE)?
