Question

O MASINA MERGE CU V1 DE 80KM/H PRIMA JUMATATE DE TIMP SI CU VITEZA DE TIMP 40KM/H V2 DE 40KM/H SA SE AFLE VITEZA MEDIE ​

Answer 1

d=d₁+d₂

d₁=d₂=d/2

t=t₁+t₂

t₁=d₁/v₁=d/2v₁

t₂=d₂/v₂=d/2v₂

vm=d/t=d/(d/2v₁+d/2v₂)=1/(v₁+v₂)/2v₁v₂=2v₁v₂/(v₁+v₂)=2*80*40/(80+40)=6400/120=53,33 km/h

vm=53,33 km/h