Concept:The mathematical derivation for the speed of sound heavily depends on thermodynamic assumptions regarding heat exchange during wave compressions.
Solution:- Sir Isaac Newton theoretically assumed that when sound waves compress and rarefy the air, heat has enough time to perfectly flow and balance out.
- Therefore, he falsely concluded that sound propagation is an isothermal (constant temperature) process.
- His resulting calculated speed (\( 280 \text{ m/s} \)) was about 16% lower than the actual speed. Pierre-Simon Laplace later corrected this by proving the rapid compressions are actually adiabatic (no heat exchange), yielding the correct speed.
Why other options are incorrect:Adiabatic (Option A) is the actual, physically correct condition discovered by Laplace, not the flawed condition originally assumed by Newton.
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