Kev faib tawm: zoo tib yam ruaj ruaj hlau nplaum rooj sib cais tau muab faib ua phab ntsa mounted hom thiab pem teb mounted yam raws li daim ntawv teeb tsa, hom yas thiab hlau hom raws cov khoom siv; hluav taws xob qhov rooj kaw tau muab faib ua ntau hom. Cov khoom lag luam txhim kho tau muab faib ua peb pawg: hom phab ntsa, hom av thiab saw hom. Raws li cov qauv sib txawv, phab ntsa hom electromagnetic qhov rooj nres tau muab faib ua hom qauv, hom nce siab, hom txuas ntxiv, kem hom, zais hom thiab ntev npab hom.