Physics - P2 (Analogue and Digital signals)

Physics - P2

Analogue signals

What are analogue signals?

Simple answer: A signal which continually varies. 

Complex answer: Information being superimposed onto an electromagnetic carrier wave to create a signal. They can vary continuously in frequency and amplitude, in the same way as the information being carried. AM and FM radio are examples.

Digital signals

What are digital signals?

Answer 1: A signal that can only take a small number of discrete values (usually two - 0 and 1). This coded information can be carried by switching the electromagnetic carrier wave off and on to create short bursts of waves (pulses) where '0' = no pulse and '1' = pulse. 

Answer 2: Information, such as sound, being transmitted digitally. The signal is converted into a code using two symbols - 0…