m4\text{m}^{4}

meter to the fourth

Area moment of inertiaexact by definition

The metre to the fourth power is the coherent SI unit of second moment of area, the purely geometric property that sets a section's bending stiffness. Its factor is 1 by construction. It is far too large for practical sections, since a steel beam's second moment of area is measured in units of 10⁻⁶ m⁴ or smaller.

Watch out: This quantity is often called the moment of inertia and written II, the same name and symbol as the mass moment of inertia in kg·m². They are unrelated: this one contains no mass and appears in δ=PL3/(3EI)\delta = PL^3/(3EI) and σ=Mc/I\sigma = Mc/I, while the mass version appears in τ=Iα\tau = I\alpha.

1 m4\text{m}^{4} 1,000,000,000,000 mm4\text{mm}^{4}

One meter to the fourth in every area moment of inertia unit

1.00000e+36nanometer to the fourth (nm⁴)
1.00000e+24micrometer to the fourth (μm⁴)
1,000,000,000,000millimeter to the fourth (mm⁴)
100,000,000centimeter to the fourth (cm⁴)
2,402,510inch to the fourth (in⁴)
115.862foot to the fourth (ft⁴)
1meter to the fourth (m⁴)this unit