Pendulum, energy conservation

Pendulum lab by PhET Interactive Simulations, University of Colorado Boulder, licensed under CC-BY-4.0 (https://phet.colorado.edu)

The title of the Project: Pendulum, energy conservation

Purpose of the work:

• Make sure that the law of energy conservation works for pendulum.

Practical part

Choose “Energy” to start the virtual experiment. 

This is a little instruction to the virtual experiment.

Virtual experiment.

Step 1. Choose the settings as depicted in the photo. 

Step 2. Release the pendulum at 90 degrees to the normal and notice how the energies change. Does the sum of potential and kinetic energies exceed the total energy at any moment? 

Step 3. Start again. Increase the friction. Release the pendulum at 90 degrees to the normal and notice how the energies change. Does the sum of potential, kinetic and thermal energies exceed the total energy at any moment? 

Step 4. Make a conclusion. 

Conclusion

The energy conservation law states that energy doesn’t disappear and appear out of nowhere, it only transforms from one type to another. In this simulation the potential energy transformed first to kinetic energy and then to kinetic and thermal energies.