Home/
Competitive Exams/
JEE Main & Advanced/
Physics/
Sound Waves/
Question 31292
JEE Physics · Hard

Sound Waves: Acoustic Impedance MCQ

Solve this quality-checked JEE multiple-choice question, then review the correct answer and explanation.

Timer-based practiceDetailed answer reviewMobile-friendly flow
Acoustic ImpedanceHardQuestion 31292

Question

Most sound is reflected when sound passes from air to water because:
  1. A
    Water absorbs sound
  2. B
    Acoustic impedances (ρv) are very different
    Correct
  3. C
    Water frequency is different
  4. D
    Density mismatch only

Correct answer

Acoustic impedances (ρv) are very different

Explanation

Acoustic impedance Z = ρv. For air Z ≈ 415 Pa·s/m. For water Z ≈ 1.5×10⁶ Pa·s/m. Huge mismatch → almost total reflection. Transmission coefficient ∝ (Z₂−Z₁)²/(Z₂+Z₁)².

Review Sound Waves notesStart timed chapter practice