Two waves have frequencies 256 Hz and 512 Hz, but same amplitude. Compare their:

(i) loudness, and

(ii) pitch.

(i) Since amplitude of two waves are same so loudness of both the waves will be same.

$\dfrac{\text{amplitude of 1st wave}}{\text{amplitude of 2nd wave}} = \dfrac{\text{1}}{\text{1}} = 1:1$

So, loudness of first wave : loudness of second wave = 1:1.

(ii) Frequency determines the pitch of the sound.

$\dfrac{\text{frequency of 1st wave}}{\text{frequency of 2nd wave}} = \dfrac{\text{256}}{\text{512}} = \dfrac{\text{1}}{\text{2}} = 1:2$

So pitch of first wave : pitch of second wave = 1 : 2.