Final answer:
Swinging limbs can be approximated by the motion of a simple pendulum, where kinetic and potential energy are interchanged during the swing. The motion principles for both are similar, though actual limb motion is more complex due to muscular action and other factors. Pendula with the same length and displacement angle have the same period, regardless of mass differences.
Step-by-step explanation:
The swinging motion of limbs can be compared to the behavior of a simple pendulum, which consists of a weight suspended by a string or rod of negligible mass. As a limb swings, it can move back and forth similar to a pendulum, experiencing cyclic motion.
Just like a pendulum, a limb in motion will have kinetic and potential energy: potential energy at the highest points of the swing due to its elevated position and kinetic energy at the lowest point due to its movement. However, in reality, limb motion is more complex due to muscle forces and air resistance.
When comparing the swinging motion of limbs to a pendulum, we must consider that a limb is not a rigid body and its mass is not concentrated at a point, which differs from the idealized model of a simple pendulum. Nevertheless, the basic principles still apply as the limb moves away from the equilibrium position, potential energy increases and kinetic energy decreases, and vice-versa as it swings back down.
For the two pendula described in the provided content, despite the different masses of Pendulum 1 and Pendulum 2, both will swing with the same period if they are the same length and are displaced by the same angle, as period is independent of mass.