Annexe C • Réponses
13.10 T = 6m p c 2 = 5,6 GeV
13.11 T e = 4004 GeV
13.12 E γ = 4m p c 2 = 3,8 GeV
13.13 (a) T p ≈ 2m π c 2 = 279 MeV
(b) T π ≈ m 2
π c 2 /2m p = 10,4 MeV
13.14 Avec β = v/c,
(a) E γ =
m π c 2
1 − β 2
2(1 − β cos θ)
(b) E max =
m π c 2 (1 + β)
2
1 − β 2
lorsque θ = 0,
E min =
m π c 2 (1 − β)
2
1 − β 2
lorsque θ = π
(c)
1 − β 2
2
(E max + E min ) =
m π c 2
2
(= E γ , lorsque v = 0)
CHAPITRE 14
14.4 (a) τ = 140 N m
(b) l = 2,8 m
(c) F ⊥ = 14 N
14.6 λ ≈ 66,6 ◦
14.7 V = 2π 2 R 3
14.8 T = Mω 2 R 2 /3
14.9 (a) x = (2R 2 /L) sin(L/2R), y = 0
(b) x = (4R/3α) sin(α/2)
14.10 x = 1,7 cm, y = 0
14.11 y = x/2
14.12 (a) F = 8,1 N
(b) x = (3
√
3/2) cm
14.13 α = arctan(1/6
√
3)
14.14 OP = 1,5
14.15 h = a(3 −
√
3)/2
14.16 x = M 1 L/(M 1 + M 2 )
14.17 P = 16mμπ 3 f 3 r 2
14.18 n = a
14.19 M = 1,8 kg
14.20 (a) ΔL = Mω 2 L/(2k − Mω 2 )
(b) Équilibre stable possible seulement si Mω 2 /k < 2.
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