Answer:
9.66 m/s 15° with +y
2.59 m/s 75° with +y
Explanation:
Momentum is conserved in the y direction.
mu₁ + mu₂ = mv₁ + mv₂
u₁ + u₂ = v₁ + v₂
10 m/s + 0 m/s = v₁ cos 15° + v₂ cos 75°
10 = v₁ cos 15° + v₂ cos 75°
Momentum is conserved in the x direction.
mu₁ + mu₂ = mv₁ + mv₂
u₁ + u₂ = v₁ + v₂
0 m/s + 0 m/s = v₁ sin 15° − v₂ sin 75°
0 = v₁ sin 15° − v₂ sin 75°
v₁ sin 15° = v₂ sin 75°
v₂ = v₁ sin 15° / sin 75°
Substitute.
10 = v₁ cos 15° + (v₁ sin 15° / sin 75°) cos 75°
10 = v₁ cos 15° + v₁ sin 15° / tan 75°
10 = v₁ (cos 15° + sin 15° / tan 75°)
v₁ ≈ 9.66 m/s
v₂ ≈ 2.59 m/s
