Computer Science for IGCSE & O level - Data Representation (Section 16)

  • 1
    When converting a negative decimal number to two's complement binary, which steps are involved?
    Antwoord
    A
    B
    C
  • 2
    What is the main disadvantage of ASCII code?
    Antwoord
    (B)
    It cannot represent non-English characters.
  • 3
    Which of the following is most closely related to the quality of an image?
    Antwoord
    (B)
    The bit depth.
  • 4
    In the context of sound, which property relates to the pitch of a sound?
    Antwoord
    (B)
    Frequency
  • 5
    When converting from binary to decimal, what operation is performed on the binary digits?
    Antwoord
    A
    B
  • 6
    Which factor primarily determines the amount of data that can be stored on a hard drive?
    Antwoord
    (B)
    The hard drive's capacity.
  • 7
    What is the decimal equivalent of the binary number 1111?
    Antwoord
    (A)
    15
  • 8
    If the most significant bit (MSB) is set to '1' in a two's complement representation, what does it typically signify?
    Antwoord
    (B)
    The number is negative.
  • 9
    Which of the following is a key characteristic of lossless compression?
    Antwoord
    (C)
    The original file can be perfectly reconstructed.
  • 10
    What is the hexadecimal equivalent of the decimal number 20?
    Antwoord
    (A)
    14
  • 11
    What will be the result of the binary addition of 1011 + 0101?
    Antwoord
    (A)
    10000
  • 12
    What is the purpose of using a higher sampling rate for digital audio?
    Antwoord
    (C)
    To capture sound more accurately.
  • 13
    What do the number of bits used to represent a pixel's colour determine?
    Antwoord
    (C)
    The number of colours possible.
  • 14
    How does two's complement representation handle negative numbers?
    Antwoord
    (C)
    By inverting all the bits and adding 1 to the result.
  • 15
    In the context of computer memory, how many bits are in a byte?
    Antwoord
    (B)
    8
  • 16
    Which factor(s) is/are directly related to the quality of a digital audio recording?
    Antwoord
    A
    B
  • 17
    If an image has a resolution of 640 x 480 pixels and a color depth of 8 bits per pixel, how many bytes of storage are required?
    Antwoord
    (B)
    (640 * 480) / 8 bytes
  • 18
    What is the smallest possible value in a 8-bit two's complement system?
    Antwoord
    (A)
    -128
  • 19
    What does a higher image resolution typically result in?
    Antwoord
    (D)
    Larger file size and more detail.
  • 20
    What type of compression is typically used to reduce the size of audio files?
    Antwoord
    (C)
    Lossy compression
  • 21
    What is the role of the leftmost bit in a two's complement representation?
    Antwoord
    (C)
    It indicates the sign (positive or negative) of the number.
  • 22
    What is the role of color depth in image file sizes?
    Antwoord
    (B)
    It impacts the number of colors represented, and therefore the file size.
  • 23
    How are HTML color codes usually written?
    Antwoord
    (C)
    Using hexadecimal numbers
  • 24
    Which of the following is a characteristic of a 'lossy' compression method?
    Antwoord
    (B)
    The file size is reduced.
  • 25
    How many bytes are used to represent an ASCII character?
    Antwoord
    (A)
    1
  • 26
    What does a hexadecimal number consist of?
    Antwoord
    (C)
    Letters A-F and numbers 0-9
  • 27
    What is the fundamental principle that allows subtraction to be performed using addition in two's complement?
    Antwoord
    (A)
    Inverting the bits and adding 1.
  • 28
    What is the process of representing sound in a digital format called?
    Antwoord
    (C)
    Digitization
  • 29
    What is the value of the hexadecimal digit 'F' in decimal?
    Antwoord
    (C)
    15
  • 30
    What is the function of the Extended ASCII character set?
    Antwoord
    (B)
    To represent non-English characters and other symbols.
  • 31
    Which color is usually represented by #FF0000 in HTML color codes?
    Antwoord
    (C)
    Red
  • 32
    What is the main difference between analog and digital signals?
    Antwoord
    (A)
    Analog signals are continuous, digital signals are discrete.
  • 33
    What are the components that determine the overall image quality of bitmap images?
    Antwoord
    A
    B
  • 34
    What does 'color depth' mean in the context of digital images?
    Antwoord
    (C)
    The number of colors that can be displayed.
  • 35
    If you double the resolution (width and height) of an image, how many times larger will the uncompressed file be?
    Antwoord
    (C)
    4 times larger
  • 36
    In digital audio, what does 'bit depth' determine?
    Antwoord
    (C)
    The accuracy of the amplitude measurements.
  • 37
    Which of the following statements about binary numbers is correct?
    Antwoord
    (C)
    Binary numbers are base-2, using only 0 and 1.
  • 38
    Which of the following are advantages of using hexadecimal over binary in computer science? (Select all that apply)
    Antwoord
    A
    C
  • 39
    In what scenarios would you choose Lossless compression over Lossy compression?
    Antwoord
    A
    B
  • 40
    What is the decimal equivalent of the binary number 10000000 in two's complement form?
    Antwoord
    (B)
    -128
  • 41
    What happens to the rightmost bits during a left bit shift?
    Antwoord
    (D)
    They are replaced by zeros.
  • 42
    What type of content is RLE compression well-suited for?
    Antwoord
    B
    D
  • 43
    Which of the following are uses of hexadecimal numbers?
    Antwoord
    A
    B
    C
  • 44
    What is the result of the two's complement conversion of -3 using 4 bits?
    Antwoord
    (B)
    1101
  • 45
    What is one of the primary applications of RLE (Run Length Encoding)?
    Antwoord
    (B)
    Compression of images with large areas of the same color.
  • 46
    What does the abbreviation 'RGB' stand for in the context of computer graphics and HTML?
    Antwoord
    (A)
    Red, Green, Blue
  • 47
    Which of the following is a characteristic of a high-quality audio file?
    Antwoord
    (C)
    A high bit depth.
  • 48
    If an image has a bit depth of 4, how many possible colors can each pixel have?
    Antwoord
    (C)
    16
  • 49
    What does increasing the resolution of an image mean in terms of pixels?
    Antwoord
    (C)
    More pixels are used to represent the image.
  • 50
    Which is a correct application of the concept of representing data in binary?
    Antwoord
    (D)
    All of the above.