Computer Science for IGCSE & O level - Data Representation (Section 14)

  • 1
    If an image is 1024 pixels wide and 768 pixels high, and the color depth is 16 bits, how many bytes are needed to store this image uncompressed?
    उत्तर
    (D)
    786432 bits
  • 2
    Which statement is generally true about a computer's logical shift operations?
    उत्तर
    (B)
    They can be used for arithmetic operations.
  • 3
    What is the most important aspect when choosing a storage device for photos?
    उत्तर
    (B)
    The storage capacity.
  • 4
    What is the advantage of using hexadecimal notation when representing binary data?
    उत्तर
    (A)
    Reduces the number of digits needed to represent binary data.
  • 5
    What are the two main components that create a Hexadecimal number?
    उत्तर
    (B)
    0-9 and A-F
  • 6
    Which is the hexadecimal representation of decimal 15?
    उत्तर
    (A)
    F
  • 7
    In ASCII, what code represents the uppercase letter 'A'?
    उत्तर
    (A)
    65
  • 8
    If you shift the binary number 11010010 two places to the right, what will be the result?
    उत्तर
    (B)
    00110100
  • 9
    Which method is suggested to convert decimal numbers into binary numbers?
    उत्तर
    (B)
    Successive division by 2 and noting the remainders.
  • 10
    Which of the following are advantages of using hexadecimal numbers over decimal numbers in computer science?
    उत्तर
    A
    B
    C
  • 11
    What is the relationship between file size, sampling rate, and bit depth for audio files?
    उत्तर
    (B)
    Increased sampling rate and bit depth usually lead to larger file sizes.
  • 12
    What is the main difference between a bitmap image and a vector image?
    उत्तर
    (A)
    Bitmap images use pixels; vector images use mathematical equations.
  • 13
    What is the binary equivalent of hexadecimal FF?
    उत्तर
    (C)
    11111111
  • 14
    Which technique is used to represent an image with less detail in order to save storage space?
    उत्तर
    (B)
    Lossy compression
  • 15
    What is the primary difference between a left bit shift and a right bit shift operation?
    उत्तर
    (A)
    Left shift multiplies; right shift divides.
  • 16
    What is the primary goal of data compression?
    उत्तर
    (C)
    To reduce the file size.
  • 17
    What is the main advantage of lossy compression for video files?
    उत्तर
    (B)
    Smaller file sizes and faster streaming.
  • 18
    What is the correct method for converting a decimal number to binary?
    उत्तर
    (B)
    Repeatedly divide by 2 and note the remainders.
  • 19
    What happens during a logical left shift?
    उत्तर
    (B)
    The bits move left, and zeros are added on the right.
  • 20
    Which of the following compression methods typically results in the smallest file size for a given image?
    उत्तर
    (C)
    Lossy compression
  • 21
    Which factors are considered when calculating the file size of an image?
    उत्तर
    A
    B
    C
  • 22
    What is the binary equivalent of the decimal number 10?
    उत्तर
    (A)
    1010
  • 23
    How is the loudness of sound represented digitally?
    उत्तर
    (B)
    By the amplitude of the sound wave.
  • 24
    What is a key advantage of using Lossless compression?
    उत्तर
    (A)
    The original quality of the content is maintained.
  • 25
    Which of the following factors is most relevant when considering image file size?
    उत्तर
    (C)
    The image's resolution.
  • 26
    What is the purpose of the headings in a typical binary number?
    उत्तर
    (B)
    To represent the position of each digit and its corresponding weight (power of 2).
  • 27
    What does the term 'sampling resolution' refer to when considering the size of an image?
    उत्तर
    (B)
    The number of bits used to represent each pixel's color.
  • 28
    Which of the following is a true statement about binary addition?
    उत्तर
    (A)
    1 + 1 = 10 (with a carry of 1)
  • 29
    How does lossless compression work to achieve file size reduction?
    उत्तर
    (B)
    By identifying and eliminating redundancy in the data.
  • 30
    Which statement is true about the conversion between lowercase and uppercase letters in ASCII?
    उत्तर
    (C)
    Converting between case requires flipping the fifth bit (from the right).
  • 31
    Which color does #800080 represent in HTML?
    उत्तर
    (A)
    Purple
  • 32
    Which of the following is most important when considering the file size of a sound file?
    उत्तर
    (C)
    The sample rate and sample resolution of the file.
  • 33
    What are the benefits of compressing files, particularly images and videos?
    उत्तर
    A
    C
  • 34
    If a pixel is represented using 1 bit, how many colors can it display?
    उत्तर
    (B)
    2
  • 35
    Which file format typically uses Lossless compression?
    उत्तर
    (C)
    PNG
  • 36
    What is a nibble?
    उत्तर
    (B)
    4 bits
  • 37
    What is the main benefit of using Run-Length Encoding (RLE) in image compression?
    उत्तर
    (A)
    It reduces the file size of images with repeating pixel values.
  • 38
    In the two's complement system, what is the result when you invert all the bits of a binary number and add 1?
    उत्तर
    (A)
    The two's complement of the original number.
  • 39
    What is the primary disadvantage of using run-length encoding (RLE)?
    उत्तर
    (B)
    It is only effective for very simple images.
  • 40
    What is the purpose of the sampling rate?
    उत्तर
    (B)
    To convert an analog signal to a digital signal
  • 41
    What is the primary purpose of MAC addresses?
    उत्तर
    (B)
    To identify devices on a network.
  • 42
    Which of the following binary numbers represents the decimal number 10?
    उत्तर
    (C)
    1010
  • 43
    What is the main function of an error code in programming?
    उत्तर
    (C)
    To provide information about an error.
  • 44
    If you want to store a large collection of high-resolution photographs, which type of storage device would be most suitable?
    उत्तर
    (B)
    A hard drive with a large capacity.
  • 45
    What is the correct sequence of steps for converting the binary number 11101011 to hexadecimal?
    उत्तर
    (B)
    Group into 4-bit segments, and then convert each segment directly to its hex equivalent.
  • 46
    What does the term 'bit depth' represent?
    उत्तर
    (C)
    The number of colors that can be displayed for each pixel.
  • 47
    What does the HTML tag represent?
    उत्तर
    (A)
    Red colored text
  • 48
    In the context of digital audio, what does 'bit depth' refer to?
    उत्तर
    (B)
    The number of bits used to represent each sample's amplitude.
  • 49
    What is a byte?
    उत्तर
    (C)
    A group of 8 bits.
  • 50
    Which is a characteristic of lossless compression techniques?
    उत्तर
    (C)
    They preserve all the original data, enabling perfect reconstruction.