Center of Mass
Drag the blue masses and watch the red center-of-mass marker follow.
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Fourier SeriesSee how adding more sine wave harmonics builds up square, sawtooth, and triangle waves.
Parachute DescentJump, then deploy the parachute and see how the descent speed slows.
Circular MotionAdjust radius and speed to see centripetal force and acceleration on an orbiting mass.
Complex Number PlaneMultiply two complex numbers and see how their magnitudes multiply and angles add on the plane.