The fig.(i) shows the graphical representation of the air molecules in a tube of air (length = L) at atmospheric pressure on the absolute pressure P(x) graph. Which one of the following pictures corresponds to the absolute pressure P(x) graph of fig. (ii).

Question

G1 Physics · Accepted Answer

Step 1: In a longitudinal sound wave, compressions correspond to pressure maxima and rarefactions to pressure minima. Step 2: Read the molecular crowding in figure (ii) and map it to the absolute-pressure variation P(x), keeping the same spatial positions of maxima/minima. The matching graph is Image 2. Final: B.