Lub luj tshib 180 degree yog ib hom luj tshib nrog lub kaum sab xis ntawm 180 degrees, feem ntau yog siv hauv cov kav dej uas yuav tsum tau hloov cov kev taw qhia thiab cov raj xa dej yuav tsum rov qab mus rau hauv keeb kwm. Vim nws lub kaum sab xis loj, nws feem ntau tsuas yog siv rau ob peb kis.
