Tiōng-le̍k-tiûⁿ

Tiōng-le̍k-tiûⁿ (重力場) sī biâu-su̍t chi̍t ê bu̍t-thé tī khong-kan tiong siū-tio̍h tiōng-le̍k chok-iōng ê tiûⁿ. Jīm-hô ióng-iú chit-liōng ê bu̍t-thé lóng ē sán-seng kap hiáng-èng tiōng-le̍k-tiûⁿ. Lán iōng tiōng-le̍k-tiûⁿ kiông-tō͘ lâi biâu-su̍t tiōng-le̍k-tiûⁿ hām bu̍t-thé chi-kan hō͘-siong chok-iōng ê sèng-chit. Tiōng-le̍k-tiûⁿ kiông-tō͘ ê tēng-gī sī:

$\mathbf {E} ={\frac {\mathbf {F} }{m}}$

Kî-tiong, F sī chit-tiám m tī tiûⁿ tiong siū-tio̍h ê tiōng-le̍k. Iû bān-iú-ín-le̍k tēng-lu̍t:

$\mathbf {F} =G{\frac {m_{1}m_{2}}{r^{3}}}\mathbf {r}$

Mā thang hó siá chò:

$\mathbf {E} =G{\frac {m}{r^{3}}}\mathbf {r}$

Chia ê m sī sán-seng tiōng-le̍k-tiûⁿ ê bu̍t-thé chit-liōng, r sī nn̄g ê bu̍t-thé chi-kan ê ūi-sí (位矢), r sī i-ê bô͘-liōng, G sī bān-iú-ín-le̍k siông-sò͘.