Annexe C • Réponses
4.14 (a) x = Vt − R sin
Vt
R
, y = R(1 − cos
Vt
R
)
(b) v x = V(1 − cos
Vt
R
), v y = V sin
Vt
R
(c) a x =
V 2
R
sin
Vt
R
, a y =
V 2
R
cos
Vt
R
4.15 v = 14,8 m s −1
4.16 (a) θ = arctan 3
(b) x = 14 m
(c) V = 19,8 m s −1
4.17 d ≈ 60 m
4.18 (a) v = 84 km h
−1
(b) a = 0,8 m s −2
4.19 a J /a R = 8/9
CHAPITRE 5
5.1 (b) a = 2g/5
(c) T 1 = (2/5) kg-poids, T 2 = (6/5) kg-poids
5.2 T = 8,8m N
5.3 T = 25 N
5.4 F =
M 2
M 1
(M + M 1 + M 2 )g
5.5 F = 392 N
5.6 a = g/9 vers le haut, T = 222 g-poids
5.7 (a) M max =
(M A + M B )D − 2M B L cos θ
4L cos θ − D
(b) t =
8L sin θ
g
5.8 g =
v 2 (2M + m)
2mh
5.9 (a) a 0 =
F − (M 1 + M 2 )g
M 1 + M 2
(b) T =
M 1
M 1 + M 2
F
(c) a = g − F/M 2 , a = g
(d) t =
√
2M 2 s/F
5.10 Δt = 0,9 s
5.11 W = 2,7 kg-poids
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