Mphamvu yachibadwa ndi mphamvu yomwe imagwira ntchito pa zinthu zomwe zakhudzana, komwe malangizo a mphamvuyo ali molunjika ku malo olumikizirana. Chizindikiro chake ndi N ndi dongosolo la mayiko osiyanasiyana ndi kg m/s2 kapena Newton.
Kanikizani N pamalo osalala
N ndi mphamvu yochokera pansi pa mtengo, N' ndi mphamvu yochokera pansi pa mtengo. w ndi mphamvu yokoka kuchitapo kanthu pa chipika kapena kulemera kwa chipikacho. N ndi N' ndi zochita, pomwe N ndi w sizili choncho. mphamvu yochitira zinthu.
Ngati chipikacho chili pamalo opumulira kapena sichikuyenda molunjika, kukula kwa mphamvu N kungawerengedwe pogwiritsa ntchito lamulo loyamba la Newton.
ΣFy = 0
N – w = 0
N = w
Ngati chipikacho chakankhidwira pansi ndi mphamvu F monga momwe zilili pachithunzi chomwe chili m'mbali, ndiye kuti kukula kwa mphamvu N ndi:
ΣFy = 0
N – w – F = 0
N = w + F
Mphamvu yachibadwa pa ndege yopendekeka
N ndi N' ndi mphamvu zochitira zinthu. N ndi mphamvu yachibadwa yomwe imagwira ntchito pa boloko ndipo N' ndi mphamvu yachibadwa yomwe imagwira ntchito pa boloko lopendekeka. W ndi gawo loyima la mphamvu yokoka (w). Mphamvu yokoka (w) imagwira ntchito pa boloko. Kukula kwa mphamvu yachibadwa ndi
ΣFy = 0
N – wy = 0
N = wy = w cos theta
