Newton originally obtained the speed of sound in a gas as vₙ = √(P/ρ). Which physical assumption about the compressions and rarefactions led to this result?
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Question

Newton originally obtained the speed of sound in a gas as vₙ = √(P/ρ). Which physical assumption about the compressions and rarefactions led to this result?

G1 Physics · Accepted Answer

Newton treated the compression and rarefaction process as isothermal. For an isothermal ideal gas, the effective bulk modulus is B = P. Therefore, vₙ = √(B/ρ) = √(P/ρ). Correct option: B.