Odpowiedzi

2013-07-02T11:10:53+02:00

dane:

sc = 2s

v1 = 80 km/h

v2 = 20 km/h

szukane:

vśr = ?

 

vśr = sc/tc

     t = s/v

     t1 = s/v1 = s/80  [h]

     t2 = s/v2 = s/20  [h]

     t = t1+t2 = s/80 + s/20 = s/80 + 4s/80 = 5s/80  [h] 

vśr = s/(5s/80)

vsr = 32 km/h

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