A taut mass less string connects two boxes as shown in the figure. The boxes are placed on an incline plane at θ = 31. What is the acceleration of boxes as they move down the incline, given m2 = 2.4 kg, m1 = 5.8 kg, μ2 = 0.10 and μ1 = 0.20.
I've tried solving this and I just don't get it.
Physics Help?
2016-02-29 5:00 pm
回答 (2)
2016-02-29 5:38 pm
Sliding down along the incline plane :
Total components of gravitational force = (m₁ + m₂) g sinθ
Total frictional force = μ₁ m₁ g cosθ + μ₂ m₂ g cosθ
Total mass = m₁ + m₂
F = m a
(m₁ + m₂) g sinθ - (μ₁ m₁ g cosθ + μ₂ m₂ g cosθ) = (m₁ + m₂) a
g[(m₁ + m₂) sinθ - (μ₁ m₁ cosθ + μ₂ m₂ cosθ) = (m₁ + m₂) a
9.81 × [(5.8 + 2.4) × sin31° - (0.20 × 5.8 × cos31° + 0.10 × 2.4 × cos31°)] = (5.8 + 2.4) a
Acceleration, a = 3.6 m/s²
Total components of gravitational force = (m₁ + m₂) g sinθ
Total frictional force = μ₁ m₁ g cosθ + μ₂ m₂ g cosθ
Total mass = m₁ + m₂
F = m a
(m₁ + m₂) g sinθ - (μ₁ m₁ g cosθ + μ₂ m₂ g cosθ) = (m₁ + m₂) a
g[(m₁ + m₂) sinθ - (μ₁ m₁ cosθ + μ₂ m₂ cosθ) = (m₁ + m₂) a
9.81 × [(5.8 + 2.4) × sin31° - (0.20 × 5.8 × cos31° + 0.10 × 2.4 × cos31°)] = (5.8 + 2.4) a
Acceleration, a = 3.6 m/s²
收錄日期: 2021-04-18 14:31:39
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