What does R stand for?

Number theory? r？ Represents the set of real numbers in set theory, and the real part of complex numbers is also represented by this symbol.

Geometric r? Or? r？ Represents the radius of a circle.

In geometry, ∠R stands for right angle.

In geometry, a right triangle can be expressed as RT△, and "RT" comes from the first two letters of the English right angle.

2. Doctor of Physics

In physical electromagnetism, italics? r？ Stands for resistance, and positive R stands for live wire.

Thermodynamic R stands for three temperature calibration methods F: Ra stands for Rankine temperature scale, re stands for Reaumur temperature scale, R&; The position of oslashR & amposlashMer temperature scale Fdgf indicates the amount of rotation (revolutions, degrees, radians) per unit time.

3. Doctor of Chemistry

R in organic chemistry is the general term for hydrocarbon chains.

In stereochemistry, R represents the right-handed (clockwise) molecular arrangement near a carbon atom, and the judgment method is based on the priority rule of Cahn Ingold Prelog.

Biochemical r stands for arginine.

R of chemical reaction? Represents the molar power generation per unit capacity.

4. Medical research

Medical r? Refers to people's breathing frequency. For example, the R ≈ 16 ~ 20 times/minute of normal people.

5. R in the computer

R of computer is an editing language for statistics. Please refer to the r language.

6. Architectural research

R of buildings is a non-metric unit of thermal resistance measurement.

7. R in Japanese

When Japanese Kanji is converted into Roman Pinyin, R is selected instead of L to represent the consonant of the pen name "ら" (line 9).