Are differential used in real life?

Answer 1

Certainly. Calculating overtime wages- some shifts pay extra as there is some social displacement- hence ( Differential for night duty) Differential Math has all kinds of applications including- automobile transmissions. Some trucks have the very neat idea of two differential shafts and differential cases ( the after part of the power train, so to speak) these counter-rotate and tame the torque to reduce needless vibration. Some Alfa-Romeo cars had this feature but it is better adapted to trucks. Cranes, too have used this split-shaft feature.