question_answer

The correct figure that shows, schematically, the wave pattern produced by superposition of two waves of frequencies 9 Hz and 11 Hz is : [JEE Main 10-4-2019 Afternoon]

A)

B)

C)

D)

Correct Answer: D

Solution :

[d]

Time period of oscillation of amplitude

Although the graph of oscillation is not given, the equation of envelope is given by option [d]