Odpowiedzi

2013-07-05T10:17:45+02:00

dane: 

sc = 2s 

v₁ = 0 km/h

v₂ = 60 km/h

szukane: 

vśr = ?

 

vśr = sc/tc

tc = t₁ + t₂

t = s/v

t₁ = s/v₁ = s/40 h

t₂ = s/v₂ = s/60 h

tc = s/40 + s/60 = 3s/120 + 2s/120 = 5s/120  h

 

vśr = 2s : 5s/120

vśr = 48 km/h

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