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The angle from vertical θ(t) at time t of a simple pendulum of mass m and length L swinging in a horizontal wind of speed V satisfies the equation

mLθ¨ = -mg sin(θ) - (1/2)rhoAC_Dv²sin(θ)
where g is the acceleration due to gravity, rho is the density of air, A is the cross-sectional area of the pendulum, C_D is the drag coefficient, and v is the wind speed.

User Alexrogers
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Final answer:

The student is inquiring about the motion of a simple pendulum under the influence of gravity and aerodynamic drag due to wind. The equation involves an interplay between gravitational forces and the wind's effect on the pendulum's oscillation. Concepts such as angular velocity, acceleration due to gravity, and trigonometry are crucial to solving pendulum dynamics problems.

Step-by-step explanation:

The student's question is about the dynamics of a simple pendulum affected by wind. The equation provided mLθ¸ = -mg sin(θ) - (1/2)rhoAC_Dv²sin(θ) represents the motion of a pendulum considering gravitational forces and aerodynamic drag due to wind.

For a simple pendulum, if we were to consider small oscillations, the motion can usually be approximated by the replacement of certain terms. The velocity 'v' is given by v=Lω, where L is the length of the pendulum and ω is the angular velocity. The spring constant 'k' is analogous to mg/L, where m is the mass and g is the acceleration due to gravity. The displacement 'x' is represented by Lθ, with θ being the angular displacement from the vertical. The equation of motion takes into account both the force of gravity and the force due to wind resistance, which is proportional to the square of the wind speed 'v', the cross-sectional area 'A' of the pendulum, the air density 'rho', and the drag coefficient 'C_D'.

The motion of a pendulum and its angular velocity at the lowest point can also be determined using these concepts. As an example, if a pendulum with certain mass and length is released from rest at an angle of 30°, one can calculate its angular velocity at the lowest point of its swing.

User Simonbs
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