Ko te rahi o te pūngao ka whakapaua ki te nuku i tētahi mea. Hei tātai i te rahi o te pūngao (arā, te nui o te mahi), me whakarea te tōpana ki te tawhiti o te nuku (i te ahunga anō o te tōpana). Ko te wae pūngoi te waeine. Arā te whārite:
M = tō × ta (M = mahi, tō = tōpana, ta = tawhiti)
The amount of energy used to move an object. The amount of work completed is calculated by multiplying the force applied by the distance moved in the direction of the force. Work is measured in joules:
W = F × d (W = work, F = force, d = distance)