The dimensionless ratio of inertial forces to elastic forces is known as the __________ number.
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Answer: B. Mach
Explanation
The Mach number is defined as the dimensionless ratio of inertial forces to elastic forces. Elastic forces within a fluid medium directly dictate the propagation speed of acoustic pressure waves. Comparing inertial forces to these elastic forces characterizes compressibility effects in high speed flows. Dimensionless numbers allow engineers to scale fluid dynamics problems across different physical dimensions. Inertial forces relate directly to fluid density and flow velocity squared through control volumes. Speed of sound in a medium represents the primary manifestation of fluid elasticity characteristics.
Aerospace engineers use the Mach number to classify subsonic transonic and supersonic flight regimes. High speed gas pipeline flow analysis requires Mach number calculations to prevent choking conditions. Compressible flow phenomena become critically important whenever fluid velocities approach local sound speed. The Reynolds number compares inertial forces to viscous forces instead of fluid elastic properties. The Euler number specifically expresses the ratio of pressure forces to inertial forces. The Weber number characterizes the relationship between inertial forces and fluid surface tension.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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