Convert Square millimetres per hour to Square metres per second

Convert Square millimetres per hour (mm²/h) to Square metres per second (m²/s) instantly and accurately.

Square millimetres per hour (mm²/h)
Square metres per second (m²/s)

Conversion Formula

m²/s = mm²/h × 2.777777778e-10

About Square millimetres per hour

The square millimetre per hour (mm²/h) equals 1/3 600 000 000 m²/s, the smallest practical thermal diffusivity unit. It is used in very slow heat-transfer processes such as diffusion through frozen soils or phase-change materials studied over many hours. Heavy clay soils can show diffusivity values of 1-2 mm²/h. 1 mm²/h = 1e-6/3600 m²/s.

About Square metres per second

The square metre per second (m²/s) is the SI unit for thermal diffusivity (α = k / ρc_p). It defines how fast a temperature disturbance propagates through a material. Diamond: ≈5 × 10⁻⁴ m²/s; silver: ≈1.65 × 10⁻⁴ m²/s; aluminium: ≈8.4 × 10⁻⁵ m²/s; iron: ≈1.8 × 10⁻⁵ m²/s; concrete: ≈6 × 10⁻⁷ m²/s; water: ≈1.4 × 10⁻⁷ m²/s. 1 m²/s = 10⁶ mm²/s = 10⁴ cm²/s.

Quick Reference Table

Square millimetres per hour (mm²/h)Square metres per second (m²/s)
1 mm²/h2.778 × 10-10 m²/s
2 mm²/h5.556 × 10-10 m²/s
5 mm²/h1.389 × 10-9 m²/s
10 mm²/h2.778 × 10-9 m²/s
25 mm²/h6.944 × 10-9 m²/s
50 mm²/h1.389 × 10-8 m²/s
100 mm²/h2.778 × 10-8 m²/s

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