Simple Pendulum Essay

Name: ISMAILA LUKMON CEG no: 08036768

Aim: Measuring a simple pendulum

Introduction:

A simple pendulum is defined as an object that has a small mass, also known as the pendulum bob, which is suspended from a wire or string of negligible mass. When displaced, a pendulum will oscillate around its equilibrium point due to momentum in balance with the restoring force of gravity.

There are many examples of pendulums around us. A swing on which a child can ride. A plumb line used by builders to obtain a true vertical measurement. A pendulum on a grandfather clock, which is calibrated to have a period of 2.0 s. A Foucault's Pendulum will demonstrate the rotation of the earth. The simple pendulum is a favourite

The period of a pendulum or any oscillatory motion is the time required for one complete cycle, that is, the time to go back and forth once. If the amplitude of motion of the swinging pendulum is small, then the pendulum behaves approximately as a simple harmonic oscillator, and the period T of the pendulum is given approximately by; T=2π√l/g

Where g is the acceleration of gravity. This expression for T becomes exact in the limit of zero amplitude motion and is less and less accurate as the amplitude of the motion becomes larger. From this expression, we can use measurements of T and L to compute g.

Variables:

Variables: In this investigation, we varied the length of the pendulum (our independent variable) to observe a change in the time period (our dependent variable). In order to reduce possible random errors in the measurements, we repeated the measurement of the time period for each of the seven lengths. We also the time for seven successive swings to further reduce the errors. The length of our original pendulum was set at 100cm for each of the following measurements, we reduced the length by

Draw the best straight line(the line that passes through most of the points plotted such that is balanced by the number of points above and below the straight line). The length of simple pendulum is directly proportional to the square of the period of oscillation. T^2 is directly proportional to L (straight line graph passing through the origin). The period of the simple pendulum oscillations increases as the length of the pendulum increases. The acceleration due to gravity can be found experimentally from the dependent period and independent length. The major source of error was damping due to friction at the point of suspension, and also due to air. Due to this friction, the total energy continuously decreases along with amplitude. Errors are also caused by the least count of the stop watch and the metre scale.

Reference: