pm là gì

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For examples of things measuring between one and ten picometres, see 1 picometre.

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A simplified representation of a helium atom, having an estimated (calculated) diameter of 62 picometres[1]

General information
Unit systemSI
Unit oflength
1 pm in ...... is equal to tướng ...
   SI base units   1×10−12 m
   Natural units   6.1877×1022 P
   1.8897×10−2 a0
   imperial/US units   3.9370×10−11 in

Look up picometre in Wiktionary, the không tính tiền dictionary.

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The picometre (international spelling as used by the International Bureau of Weights and Measures; SI symbol: pm) or picometer (American spelling) is a unit of length in the International System of Units (SI), equal to tướng 1×10−12 m, or one trillionth (1/1000000000000) of a metre, which is the SI base unit of length.

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The picometre is one thousand femtometres, one thousandth of a nanometre (1/1000 nm), one millionth of a micrometre (also known as a micron), one billionth of a millimetre, and one trillionth of a metre.[2] The symbol μμ was once used for it.[3] It is also one hundredth of an ångström, an internationally known (but non-SI) unit of length.


The picometre's length is of an order sánh small that its application is almost entirely confined to tướng particle physics, quantum physics, chemistry, and acoustics. Atoms are between 62 and 520 pm in diameter, and the typical length of a carbon–carbon single bond is 154 pm. Smaller units still may be used to tướng describe smaller particles (some of which are the components of atoms themselves), such as hadrons and the upper limits of possible size for fermion point particles.

The laze Interferometer Space Antenna (LISA) probe is planned for launch in 2034 to tướng directly detect gravitational waves and will measure relative displacements with a resolution of trăng tròn picometres over a distance of 2.5 gigametres, yielding a strain sensitivity of better than thở 1 part in 1020.