Home / IBDP Physics- C.5 Doppler effect- IB Style Questions For SL Paper 2

IBDP Physics- C.5 Doppler effect- IB Style Questions For SL Paper 2 -FA 2025

IBDP Physics SL Paper 2 -FA 2025- All Chapters

Question

Sound of frequency \( f = 2500 \,\text{Hz} \) is emitted from an aircraft that moves with speed \( v = 280 \,\text{m s}^{-1} \) away from a stationary observer.
The speed of sound in still air is \( c = 340 \,\text{m s}^{-1} \).
C.5 Doppler effect Paper 2
(i) Determine the frequency heard by the observer. [2]
(ii) Determine the wavelength measured by the observer. [1]
• Topic C.5: Doppler effect — parts (i), (ii)
▶️ Answer / Explanation
(i)

For a source moving away from the observer,
\( f’ = f \left( \frac{c}{c + v} \right) \)

\( f’ = 2500 \times \frac{340}{340 + 280} \)

\( f’ = 1371 \,\text{Hz} \approx 1.4 \times 10^{3} \,\text{Hz} \)

 

(ii)

\( \lambda = \frac{c}{f’} = \frac{340}{1371} \)

\( \lambda \approx 0.25 \,\text{m} \)

More C.5 Doppler effect SL Paper 2 Questions..
Scroll to Top