所有的物理推导公式
o==)_\
| ',====_
`======== \ \ \_____
(________)/~-----||-----.\ \ `\ ||
_\_\__/_______||______\ \ \ `\||
(||__________________ \ | |) `\_
/ /_~_/// \ / / / `-_
/ -==============- / / / / ___________\_
/_____________==//___/_/________/_/___===========|
_//| ( () )/ `-----------------' | ( ()') |
'-' \_ `--' _/ \_ `--' _/
`----' `----