Using A Pendulum To Measure Gravity's Acceleration

SCIENCE CONCEPT:

It is difficult to directly measure the acceleration due to gravity. However, it is possible to indirectly measure gravity very accurately using a pendulum. The time it takes a pendulum to complete one back-and-forth swing, called the pendulum's period, depends only on the pendulum's length, and the value of gravity. In this experiment, you will obtain experimental values of periods for pendulums of different lengths.

STUDENT OBJECTIVE:

The student will explore the measurement of gravity using a pendulum.

OVERVIEW:

In this activity, the student will calculate the measurement of gravity using a pendulum made from washers, a ring stand, string, a spring clamp, 2 small pieces of wood, and a protractor.

PREPARATION TIME:

20 minutes.

LESSON TIME:

30 minutes.

TEACHER PREP:

Gather materials that are needed for the experiment.

WORDS TO KNOW:

acceleration

gravity

value of gravity

center of gravity

suspension

friction free

jaws of a clamp

value

TEACHER TEXT:

The story is told that while Sir Isaac Newton was in his garden an apple fell on his head from a tree. The great scientist immediately began to wonder what caused the apple to fall while the sun, moon, and other stars remained overhead and showed no tendency to follow the apple.

The theory of gravity for which Newton is now famous proves valuable in many aspects of our modern life. Airplanes have to be so constructed and powered that they can successfully resist the force of gravity. Cars and trucks, and especially tall vehicles, have to be made with their centers of gravity low enough to withstand any tendency to topple over when driven around sharp corners. Designers and engineers have to work out complicated mathematical formulae to discover the center of gravity of the product they are working on.

Just as important is the gravity's acceleration rate. All of science is bound in one way or another by gravity. In this experiment you will be measuring the acceleration of gravity.

Web Hosting Provided By The National Business Aviation Association.

Explore Space ... Not Drugs!
Hear what astronauts have to say about staying drug-free.
Last modified: Tue Mar 24 16:53:26 PST 1998