Pendulum With Large Oscillation

Purpose

To show the difference between pendula with small amplitude and large amplitude of oscillation, and to show rotational motion where the kinetic energy at the top is much less than the change of potential energy from the top to the bottom of the oscillati

Equipment

Oberbeck Cross, wooden block

Images

g1-16

Description

The Oberbeck Cross is used with three of the weights removed and one at its maximum radius. The motion of the pendulum for various amplitudes, including complete rotation, can be simply observed or can be compared with computer simulations of the 360 degree pendulum. Because of the large change of potential energy, the velocity of the bob changes significantly when it is given just enough energy to undergo full circular oscillations.◙

References

George E. Owen and Daniel C. Mckown, An Experiment Illustrating the Elliptic Integral of the First Kind, AJP 19, 188, (1951). ◙James L. Anderson, Approximations in Physics and the Simple Pendulum, AJP 27, 188-189, (1959). ◙Harry H. Denman, Amplitude-Dependence of Frequency in a Linear Approximation of the Simple Pendulum Equation, AJP 27, 524-525, (1959). ◙Malcolm K. Smith, Precision Measurement of Period vs. Amplitude for a Pendulum, AJP 32, 632-633, (1964). Douglas J. Haddad, Instructional Uses of the Computer: Simple Pendulum Experiment, AJP 36, 273, (1968).