Odpowiedzi

2009-04-10T18:50:23+02:00
T1=s/(2v1)
t2=s/(2v2)
t1+t2=s/2*(1/v1+1/v2)=s/2[(v1+v2)/v1v2]

V=s/(t1+t2)=2*v1v2/(v1+v2)
V=2*60*80/140=960/14=68,57km/h
odp V=68,57km/h