Newton's formula for the speed of sound in air (assuming isothermal process) predicted a value about 15% lower than the observed value. The correction was made by
A{'text': 'Kepler', 'label': 'A'}
B{'text': 'Laplace', 'label': 'B'}
C{'text': 'Doppler', 'label': 'C'}
D{'text': 'Huygens', 'label': 'D'}
Answer & Solution
Correct answer: B. {'text': 'Laplace', 'label': 'B'}
1. Newton assumed isothermal conditions for sound propagation.
2. Laplace pointed out that compressions/rarefactions are too fast for heat exchange.
3. So the process is adiabatic, giving v = √(γP/ρ).
4. This adiabatic correction brings the theoretical value in agreement with the experimental 331 m/s at 0°C.
_Source: NCERT Class 11 Physics, Ch 14 "Waves", §14.4_
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