The longitudinal-wave speed in a taut brass wire is 100 times its transverse-wave speed. If Young's modulus of brass is 1.0 × 10¹¹ N m⁻², find the stress in the wire.
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The longitudinal-wave speed in a taut brass wire is 100 times its transverse-wave speed. If Young's modulus of brass is 1.0 × 10¹¹ N m⁻², find the stress in the wire.

G1 Physics · Accepted Answer

Step 1: vL = √(Y/ρ) and vT = √(σ/ρ), where σ is tensile stress. Step 2: vL/vT = √(Y/σ)=100, so Y/σ = 10⁴. Step 3: σ = 10¹¹/10⁴ = 10⁷ N m⁻². Final: A.