WJEC DigiTech GCSE - Data

What is an example of analogue data?

• A digital clock

• A vinyl record

• A computer file

• A smartphone app

How do computers represent data?

• As grooves on a disk

• As a combination of 1 or 0 numbers

• As sound waves

• As physical shadows

What process is used to store sound digitally?

• Engraving

• Sampling

• Printing

• Painting

What does the blue line represent in the graph of analogue audio sampling?

• Digital samples

• Analogue sound wave

• Sampling frequency

• Compressed data

What is the typical sampling frequency used on most audio CDs?

• 22,000 times per second

• 44,000 times per second

• 88,000 times per second

• 11,000 times per second

Why might sound sampled at 44 kHz in stereo need to be compressed?

• To increase the sampling frequency

• To reduce the data size

• To improve sound quality

• To convert to analogue

What is an example of analogue data that can be stored?

• Binary code

• Voltage

• Text files

• Digital images

What is an example of a non-electrical analogue device?

• Analogue synthesiser

• Digital clock

• Analogue clock

• Digital synthesiser

Which of the following is a disadvantage of digital data?

• Requires more physical space

• Data is not recorded in its entirety

• Continuous data quality is lost

• Data is always more accurate

What is the function of an analogue-to-digital (A/D) converter?

• Converts digital signals into analogue signals

• Converts continuous signals into discrete digital numbers

• Converts electrical signals into mechanical signals

• Converts analogue signals into electrical charges