Our main concern so far has been to say if we have a conservative force field it means that the work of a force is the change in the energy.

目前为止，我们主要关心的是，如果在保守力场中，力所做的功是，能量的改变。

youdao

The article proceeds from the characteristic of doing work of electrostatic field strength and proves that electrostatic field is a conservative force field.

文章从静电场力作功的特点出发，说明静电场是保守力场。

youdao

So, what that means concretely is if you have a force field that conservative, then you cannot build somehow some perpetual motion out of it.

具体来讲，如果你有一个保守力场，就不可能建立起永恒的运动。

youdao

However, the Ulster Unionists have ruled out any merger with the DUP and restated their commitment to their electoral pact with the Conservative Party, where they will field joint candidates under the banner Ulster Conservatives and Unionists - New Force (UCUNF).

BBC: UUP will not 'rush deal decision'