1> (a) d(1) = - 120 i km
d(2) = 140 j km
d(3) = 180 . cos 60 i + 180 . sen 60 j = 90 i + 155,88 j km
(b) d(R) = - 120 i + 140 j + 90 i + 155,88 j = - 30 i + 295,88 j km
(c) d(R) = Raiz quadrada ( 30 ˆ2 + 295,88ˆ2) = 297,4 km
(d) teta = tgˆ-1 (295,88 / 30) = 84º => 180 - 84 = 96º
2> (a) y = g tˆ2/2 => 65 = 10 tˆ2/2 => t = 3,6 s
(b) v = g t => 10 . 3,6 = 36 m/s
(c) y = gtˆ2/2 = 10 . 2,6ˆ2 / 2 = 33,8 m => 65 - 33,8 = 31,2 m
3> (a) Delta t(1) = Delta s 1 / vm 1 = 450 / 340 = 1,32 h
(b) Delta t(2) = Delta s 2 / vm 2 = 150 / 280 = 0,54 h
(c) vm = 600 / 1,86 = 322,58 km/h
4> (i) a + b = - 4i - 8 j (m)
(ii) vox = vo cos teta = 200 cos 40 = 153,21 m/s
voy = vo sen teta = 200 sen 40 = 128,56 m/s
A = voˆ2 . sen 2 teta / g = 200ˆ2 . sen 80 / 10 = 3939,23 m
H = (vo sen teta )ˆ2 / 2 g = (200 . sen 40)ˆ2 / 2 . 10 = 826,35 m
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