Katie Flanagan- Pendulums

Title:

Pendulums

Principles Investigated:

Potential and Kinetic Energy, Earth's Rotation, Foucalt's Pendulum, Gravity, Inertia, Gravitational Acceleration, Law of Conservation of Energy

Standards:

8 Framework: Students should begin to grasp four concepts that help to unify physical sciences: Force and energy; the laws of conservation...

Materials:

- 1 computer per student

- Pendulum Phet Simulator link on each computer

- Access to the google form on each computer

- 1 pendulum to demonstrate

> stand

> string

> 5 washers

> protractor

> stopwatch

Background Information:

- Potential Energy-- The energy stored as the result of an object's position.

- Kinetic Energy-- The energy of motion

Need to Know:

Why is a pendulum Scientifically important?

- Can be used to provide accurate time keeping

- It can be used to measure "g", the acceleration due to gravity

- It can be used to show that the earth spins

So how does a pendulum do all that?

Let's Find Out!

Procedures:

A pendulum is a device that measures Periodic (Harmonic) Motion. Below is a picture of a pendulum.

The experiment that you are going to do today is going to determine what effects the speed of the bob at the end of the pendulum (or the period of the pendulum).

You will be doing two different experiments to determine how the length and the mass of the bob effect the period of the pendulum.

You will be using a pendulum simulator to do this experiment. Click here to open the simulator.

You will be recording your hypothesis, data, and conclusions in the form by clicking here.

Follow each of the procedures on the form to complete the experiment.

Experiment 1: Mass of bob

Experiment 2: Length of rod

** How would the period of the pendulum change if the pendulum was on the moon? Using the same simulator, change the dot from the Earth to the Moon. Record your findings on the record sheet.

Real Life Application:

Foucault's Pendulum- The Earth's Rotation

Simulation of the pendulum on the North Pole showing the Earth's Rotation. Click Here

So as you can see in the equation... Length is the only variable that effects the period of the pendulum other than gravitational acceleration.

Resources:

How does a pendulum work? www.calacademy.com

Phet Simulations http://phet.colorado.edu/en/simulations/category/new