Falling Filters Model

Students not only use this model to investigate Newton's second law and the effects of drag, they also use the model to compare theoretical and experimental results. The graphs below show the comparison of freefall and two different cross-sectional areas. Note the feedback loop indicated in green.

 THE MODEL
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[Diagram Level | Equations Level | Graphs ] ```Displacement(t) = Displacement(t - dt) + (Rate_of_Change_of_Displacement) * dt
INIT Displacement = 1.5 {m}
Rate_of_Change_of_Displacement = Velocity
Velocity(t) = Velocity(t - dt) + (Rate_of_Change_of_Velocity) * dt
INIT Velocity = 0 {m/s}
Rate_of_Change_of_Velocity = Acceleration
Acceleration = Net_Force/Mass
acceleration_due_to_gravity = -9.8 {m/s^2}
air_density = 1.16 {kg/m^3}
Applied_force = weight
cross_sect_area = 0.0133 {m^2}
drag = 0.5*drag_coefficient*air_density*cross_sect_area*Velocity^2
drag_coefficient = 1
Mass = 0.00105 {kg}
Net_Force = Applied_force+Opposing_Force
Opposing_Force = drag
weight = Mass*acceleration_due_to_gravity

```
##### Time Specs Settings
Range: 0-2 ; dt = 0.05; Integration Method = Runge-Kutta 4   Home | Contact | Site Map | Search