AQA GCSE Computer Science - 3.3.7 Representing Sound

Are analogue and digital sounds continuous or discrete

• Analogue is continuous, Digital is discrete

• Both are continuous

• Analogue is discrete, Digital is continuous

• Both are discrete

What does ADC stand for?

• Analogue-to-Digital Converter

• Alternating Direct Current

• Analogue Data Compression

• Arithmetic Data Calculation

Which is file size not increased by?

• Sample accuracy
• Sample resolution
• Sample length (seconds)
• Sample rate

CDs are typically sampled at:

• 44.1kHz
• 441kHz
• 4,410kHz
• 4.41kHz

What is sample resolution?

• The accuracy of the amplitude used to to record each measurement

• The accuracy of the wavelength used to record each measurement

• The the accuracy of the period used to record<br />each measurement

• The accuracy of the wave speed used to record each measurement

What is the file size of a 3-second long recording with a resolution of 4 bits at 8 samples per second?

• 12 bytes

• 6 bytes

• 12 bits

• 6 bits

What is the range of human hearing?

• 20-20,000Hz

• 20-20,000kHz

• 20-19,998Hz

• 20-19,998kHz

What does lossy compression usually do (to audio recordings)?

• Remove unecessary sound from outside the range of human hearing.

• Leave out repeated data.

• Reduce the sample resolution

• Reduce the sample rate

What kind of form of digital signal is sound converted to with a microphone

• Binary
• ASCII
• Unicode
• MIDI

What type of file would a .wav format be used for?

• Uncompressed files

• Lossy compressed files

• Losslessly compressed files

• Any compressed file