Orders of magnitude (torque)
Comparison of a wide range of torques
From Wikipedia, the free encyclopedia
The following are examples of orders of magnitude for torque.
Examples
| Order of magnitude | Value | Item | |
|---|---|---|---|
| SI units | Imperial units | ||
| 10−36 | 3.9 × 10−36 N⋅m | Computed radiative torque on a model interstellar dust grain — an irregular silicate grain 0.2 μm across — spun by the anisotropy of ambient starlight in the local interstellar radiation field. This torque drives grains to rotation rates hundreds of times faster than thermal, and underlies the polarization of starlight and the alignment of grains with the Galactic magnetic field.[1] | |
| 10−24 | 9.27 × 10−24 N⋅m | Torque on a magnetic dipole of one Bohr magneton oriented perpendicular to a 1 tesla magnetic field. This is a characteristic scale rather than a measured value: the expression τ = μ × B is semi-classical; quantum-mechanically, the torque causes Larmor precession rather than a mechanical twist.[2] | |
| 10−20 | 4 × 10−20 N⋅m | Torque generated by a single molecule of F1-ATPase, the rotary catalytic subcomplex of ATP synthase, while hydrolysing ATP.[3] | |
| 10−12 | 3 × 10−12 N⋅m | 2.2 × 10−12 lb⋅ft | Peak aerodynamic pitching torque about the centre of mass of the featherwing beetle Paratuposa placentis, one of the smallest known insects, at 2.43 μg body mass and 395 μm body length. Its bristled wings — setae rather than membrane over 95% of the wing area — beat at 177 Hz in a figure-of-eight cycle at a Reynolds number near 9, where air behaves as a viscous fluid and the gaps between the bristles effectively close.[4] |
| 10−9 | 2 × 10−9 N⋅m | 1.5 × 10−9 lb⋅ft | Peak aerodynamic yaw torque generated by a fruit fly (Drosophila melanogaster) during a rapid turning manoeuvre, produced by subtle asymmetries in wing motion.[5] |
| 10−7 | 3 × 10−7 N⋅m | 2 × 10−7 lb⋅ft | Gravitational torque on the torsion balance in the 1798 Cavendish experiment, the first measurement of the density of the Earth: 158 kg lead spheres attracting two 0.73 kg balls mounted on a 1.83 m rod.[6] |
| 10−5 | 2 × 10−5 N⋅m | 1.5 × 10−5 lb⋅ft | Torque generated by the hygroscopic awn of a Pelargonium seed as it coils, drilling the seed into the soil; the awn coils when dry and uncoils when wet, converting the day–night humidity cycle into rotation.[7] |
| 10−3 | 3.3 × 10−3 N⋅m | 2.4 × 10−3 lb⋅ft | Maximum torque delivered by the mainspring barrel of a mechanical wristwatch movement.[8] |
| 10−2 | 1.1 × 10−2 N⋅m | 8 × 10−3 lb⋅ft | Net torque spinning up the asteroid Bennu, from a measured rotational acceleration of 2.64 × 10−6 deg/day2; consistent with the YORP effect, the recoil of thermally re-radiated sunlight from an irregularly shaped body.[9] |
| 100 | 1 N⋅m | 0.73 lb⋅ft | Torque when one end of a 1 m long moment arm is acted upon by a force of 1 N. |
| 4.1 N⋅m to 6.6 N⋅m | 3.0 lb⋅ft to 4.9 lb⋅ft | Torque required to open a vacuum-sealed glass jar with a 65 mm or 85 mm lid. Ergonomic studies have proposed limiting this to 2 N⋅m, which most adults over 50 can exert.[10] | |
| 102 | 108 N⋅m to 149 N⋅m | 80 lb⋅ft to 110 lb⋅ft | Torque to which most lug nuts are tightened.[11] |
| 881 N⋅m | 650 lb⋅ft | Torque at the crankshaft of a Dodge Charger SRT HellCat.[12] | |
| 104 | 13,000 N⋅m | Example 2 MW wind turbine, generator side.[13] | |
| 106 | 1,300,000 N⋅m | Example 2 MW wind turbine, blade side.[13] | |
| 7,000,000 N⋅m | 5162935 lb⋅ft | Output torque of the Wärtsilä RT-flex96C,[14] the largest piston engine in the world. | |
| 109 | 2.45 × 109 N⋅m | 1.8 × 109 lb⋅ft | Maximum rated load moment of the Sarens SGC-250 ring crane ("Big Carl"), 250,000 tonne-force-metres, one of the largest land-based cranes ever built.[15] |
| 1016 | 4.5 × 1016 N⋅m | 3.3 × 1016 lb⋅ft | Secular tidal torque of the Moon on the Earth, which slows Earth's rotation and drives lunar recession.[16] |
| 1019 | 1.0 × 1019 N⋅m | 7.7 × 1018 lb⋅ft | Anomaly in the global mountain torque between the atmosphere and the solid Earth during the 1997–1998 El Niño: 10.4 Hadley, where 1 Hadley = 1018 N⋅m. Atmospheric pressure bearing unevenly on the world's mountain ranges transfers angular momentum to the atmosphere, lengthening the day by up to 0.9 ms.[17] |
| 1023 | 3.3 × 1023 N⋅m | 2.4 × 1023 lb⋅ft | Braking torque exerted on the Sun by the solar wind, measured in situ by the Wind spacecraft; independent estimates span roughly 2–3.3 × 1023 N⋅m. The Sun's magnetic field grips the escaping wind out to the Alfvén surface, carrying angular momentum away and slowing the Sun's rotation.[18] |
| 1029 | 2.4 × 1029 N⋅m | 1.8 × 1029 lb⋅ft | Electromagnetic spin-down torque on the Crab Pulsar, from its measured rotation frequency and spin-down rate. Assumes the canonical (conventional approximation) of 1038 kg⋅m2 for the neutron star moment of inertia.[19] |
| 1032 | 8 × 1032 N⋅m | 6 × 1032 lb⋅ft | Minimum mean torque on the crust of the Vela Pulsar during its 2016 glitch. A lower bound, since the rise time is an upper limit; an internal torque, so the star's total angular momentum is conserved; assumes the canonical neutron star moment of inertia of 1038 kg⋅m2.[20] |