Odpowiedzi

2009-10-18T21:59:07+02:00
T 1 = 30 min = 1/2 h
v1 = 30 km/h
s1 = vt
s1 = 30 km/h x 1/2 h = 15 km

t2 = 1,5 h
v2 = 50 km/h
s2 = 50 km/h x 1,5 h = 75 km

v sr = sc/tc
sc = 15 km + 75 km = 90 km
tc = 1,5 h + 0,5 h = 2h

vśr = 90 km / 2h = 45 km/h

srednia szybkosc tego samochodu to 45 km/h