Four sound sources produce the following four waves
(i) `y_(1)=a sin (omega t+phi_(1))`
(ii) `y_(2)=a sin 2 omega t`
(iii) `y_(3)= a' sin (omega t+phi_(2))`
(iv) `y_(4)=a' sin (3 omega t+phi)`
Superposition of which two waves gives rise to interference?

Options

A. (i) and (ii)
B. (ii) and (iii)
C. (i) and (iii)
D. (iii) and (iv)

Answer

C

Explanation

According to the principle of superposition, the resultant displacement is the algebraic sum of the individual displacements. (i) and (iii) have same frequency