alleryStart learning →Thermal diffusivity α is defined as:
A$\alpha = k$
B$\alpha = k/(\rho c_p)$ (m²/s) — ratio of conduction transport to thermal storage capacity
C$\alpha = h/k$
D$\alpha = c_p T$
Answer & Solution
Correct answer: B. $\alpha = k/(\rho c_p)$ (m²/s) — ratio of conduction transport to thermal storage capacity
α = k/(ρc_p), m²/s.
**Appears in the heat equation:** $\partial T/\partial t = \alpha \nabla^2 T + \dot{q}/(\rho c_p)$.
Materials with high α (metals) respond quickly to temperature changes
insulators have low α.
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