Four light sources produce the following four waves
(i) `y_(1) = a sin (omegat + phi_(1))`
(ii) `y_(2)= asin2 omegat`
(iii) `y_(3) = a^(‘) sin (omegat + phi_(2))`
(iv) `y_(1) = a sin (omegat + phi_(1))`
Superposition of which two waves give rise to interference?

Options

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

Answer

c

Explanation

To obtain sustained interference between two waves source must propagate in same direction and have equal frequency.