Falling rods

Two rods are dropped over a smooth table. In one case the end point on the table can slide without friction, while in the other case it may rotate around a horizontal smooth articulation. The simulation allows computing fall times and trajectories.

You can select below the initial position of both rods by using the slider or entering its initial slope as given by the angle phi with the horizontal.
Unit time is (L/g)^1/2, where L is rods' length.
Put the mouse pointer over an element to get information about it.

Activities

Compute the angular velocity of each rod when its angle with the horizontal is 0 ≤ φ ≤ phi < π/2. Which rod will fall faster?
Press Start to check your guess.
Which is the geometrical form of the trajectories of the center point and upper end of the right rod?
Check Trajectories and run again the simulation to check your guess.

This is an English translation of the Basque original for a course on mechanics, oscillations and waves.
It requires Java 1.5 or newer and was created by Juan M. Aguirregabiria with Easy Java Simulations (Ejs) by Francisco Esquembre. I thank Wolfgang Christian and Francisco Esquembre for their help.