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Projectile motion with air drag

What you are seeing: three projectiles fired simultaneously at the same speed v0v_0 and angle θ\theta, subject to different drag laws. The yellow projectile is in vacuum (no drag); the cyan one experiences Stokes drag F=bvF = -b\mathbf{v}; the orange one experiences quadratic drag F=cvvF = -c|\mathbf{v}|\mathbf{v}. All three leave the launcher at the same time but land at different ranges.

Without drag the trajectory is a parabola with range R=v02sin(2θ)/gR = v_0^2 \sin(2\theta) / g (max at θ=45\theta = 45^\circ). Stokes drag is linear and falls off more gently with speed; quadratic drag grows faster at high speed, so it bites harder near launch. Slide the speed and angle to see the asymmetry: at high speeds quadratic drag dominates; at low speeds Stokes drag wins.

Figure 1. Projectile with three drag laws (vacuum, Stokes, quadratic). Method: RK4 integration; the capture spans the vacuum flight.
v_0 (m/s)20
angle45 deg
speed2

WHAT TO TRY

  • Vary each control and watch the rail readouts respond.
  • Compare the diagnostic plot against the live scene.