Answer to Question #165094 in Astronomy | Astrophysics for Rasgel

Question

The equation y = Asin (wt + kx) represents a progressive wave.

(a) What do the quantities A, w and k represent?

(b) In which direction is the wave moving? (Explain how you arrived at your conclusions) 

Answer 1

(a) $A$ represents the amplitude of the wave, $\omega$ represents the angular frequency of the wave and $k$ represents the wave number of the wave.

(b) The general equation of the progressive wave can be written as follows:

$$y=Asin(\omega t \mp kx),$$

here, sign minus corresponds to the wave traveling in +$x$-direction and sign plus correspond to the wave traveling in -$x$-direction.

Therefore, in our case the wave moves in -$x$-direction.