Cov ntawv xuab zeb puas tuaj yeem ua av qhuav?

Water sandpaper tseem hu ua dej sandpaper. Raws li lub npe qhia, nws yog av thiab ua tiav los ntawm kev sib tsoo dej. Nws feem ntau yog immersed nyob rau hauv dej los yog sanded nyob rau hauv dej. Cov ntawv xuab zeb puas tuaj yeem qhuav sanded?

Feem ntau hais lus, cov ntawv xuab zeb tuaj yeem qhuav sanded, tab sis nws tsis pom zoo, feem ntau vim tias yog cov ntawv xuab zeb qhuav qhuav, cov nplua yuav nyob twj ywm hauv qhov khoob ntawm cov xuab zeb nplej, ua rau saum npoo ntawm cov ntawv xuab zeb ci, kom nws tsis tuaj yeem ua tiav. nws vim. nyhuv. Tsis tas li ntawd, cov xuab zeb qhuav nrog dej xuab zeb yuav ua rau cov ntawv xuab zeb dej puas sai sai thiab cuam tshuam rau nws lub neej kev pab. Yog li ntawd, qhuav sanding nrog dej sandpaper tsis pom zoo.