Pendulum Physlet

The equation of motion for a damped, sinusoidally driven pendulum in the earth's gravitational field is,

m L d2q/dt2 + g dq/dt + m g sin q = A sin( w t)

where q is the angle with respect to the vertical, m is the mass, L is the length, g is the acceleration of gravity and g is the damping. The driving force has amplitude A and driving frequency omega, w. Choosing units such that m, L, and g are all one, i.e., so called scaled units, simplifies the equation to:

d2q/dt2 + g dq/dt+ sin q = A sin( w t).

The Pendulum Physlet solves this differential equation using a 4th order Runge-Kutta algorithm.

Note: Click inside the applet and press the spacebar to stop the animation.

Press the tab key to clear the phase and time graphs. This is useful to remove transients.



Visit the Physlets Page or contact Wolfgang Christian