Question

In frequency modulated wave

• A. frequency varies with time
• B. both frequency and amplitude vary with time
• C. amplitude varies with time
• D. both frequency and amplitude are constant

Answer 1

Answer: (A)

In frequency modulated wave, only frequency varies with time, while the amplitude remains constant. This wave can be shown as

It is used in $FM$ broadcasting, telemetry and $RADAR$ etc.