IB Physics HL C.5.5 Mechanical-wave Doppler formulas Question Bank

Practise IB Physics HL C.5.5 by applying mechanical-wave doppler formulas concepts to exam-style physics questions.

Exam points

identify the relevant physical quantity, model or diagram
apply the correct equation and units to the evidence
justify the result using conservation laws, fields or energy relationships

[Maximum number: 2]

Two loudspeakers, A and B, are driven in phase and with the same amplitude at a frequency of 850 Hz . Point P is located 22.5 m from A and 24.3 m from B. The speed of sound is $340 \mathrm{~ms}^{-1}$ .

Figure for Question C.5.5 (HL)—Mechanical-wave Doppler formulas question 1 — IB Physics HL

In another experiment, loudspeaker A is stationary and emits sound with a frequency of 850 Hz . The microphone is moving directly away from the loudspeaker with a constant speed v. The frequency of sound recorded by the microphone is 845 Hz .

Calculate v.

$\begin{aligned} 845=850 \times \frac{340-v}{340} v=2.00<\mathrm{m} \mathrm{~s}^{-1}>- \end{aligned}$

All question bank results loaded

C.5.5 (HL)—Mechanical-wave Doppler formulas question 1