82. AQA GCSE (8525) SLR13 – 3.3 Sound

What is sound?

• A digital signal

• A color spectrum

• A vibration that propagates as an audible wave of pressure

• A type of energy drink

Answer explanation

Sound is a vibration that propagates as an audible wave of pressure, making it the correct choice among the options provided.

How is sound detected?

• Through a camera

• By a thermometer

• Using a microphone or the human ear

• With a barometer

Answer explanation

Sound is detected using a microphone or the human ear, which can convert sound waves into electrical signals that are then interpreted as sound.

What is the process of converting an analogue signal into a digital binary one called?

• Digital to analogue conversion

• Binary processing

• Signal modulation

• Analogue to digital conversion

Answer explanation

The process of converting an analogue signal into a digital binary one is called Analogue to digital conversion.

What affects the quality of a digitally converted sound wave?

• Color depth

• Sample rate and sample resolution

• Brightness level

• Pixel density

Answer explanation

The quality of a digitally converted sound wave is affected by the sample rate and sample resolution, not color depth, brightness level, or pixel density.

What is the sample rate?

• The bitrate of a video

• The resolution of a digital image

• The speed of sound

• How often an audio analogue sound wave is sampled

Answer explanation

The sample rate refers to how often an audio analogue sound wave is sampled, capturing the data points of the wave at regular intervals.

What does the sample resolution determine?

• The size of the sound file

• The color depth of an image

• The level of detail in a digital waveform

• The speed of data transfer

Answer explanation

The sample resolution determines the level of detail in a digital waveform, not the size of the sound file, color depth of an image, or speed of data transfer.

What is a sound sample?

• A type of musical instrument

• A playlist

• A free music track

• A sound converted to binary

Answer explanation

A sound sample is a sound converted to binary, representing the audio data in a digital format for storage or processing.

How is the sample rate measured?

• In lumens

• In decibels

• In Hertz

• In pixels

Answer explanation

The sample rate is measured in Hertz, which represents the number of samples taken per second. It is a unit of frequency used to quantify the rate of audio signal sampling.

What sample rate is used for a music CD?

• 8000 Hertz

• 22050 Hertz

• 44100 Hertz

• 96000 Hertz

Answer explanation

The correct sample rate used for a music CD is 44100 Hertz, which is the industry standard for audio CDs.

What does a higher number of samples per second indicate?

• Lower quality sound

• Higher quality sound

• Faster playback speed

• Shorter sound duration

Answer explanation

A higher number of samples per second indicates higher quality sound because it captures more detail and nuances in the audio signal.