Work and Energy Free Exploration
Individual Support Required for all Explorations

 Video Clips – These have informational clips as well as things to do involving the phenomena in the video. Notes are needed as support.
There are three sets of clips. Each dealing with work, conservation of energy, and simple machines

Hewitt lecture/demo Clips – These are mostly short demos. Paul Hewitt is a Professor of Physics in San Francisco and Hawaii. Notes are needed as support.
Conservation of energy and Pulleys
Full Length Hewitt Videos – Full 30+ minute lectures by Hewitt (the clips came from here). Notes are needed as support.

Energy - 44 minutes

Crate of Knowledge mini Labs - these activities have procedures which can be found in the Crate of Knowledge.
Measuring Power - use different types of cylinders to measure the power of lifting an object.
Weighing coins with a lever - make and use a paper lever to determine the mass and weight of various coins
Pulleys - explore the mechanical advantage of pulley systems with one to seven pulleys
Balancing lever - use the idea of work to balance out a lever
Gears - explore gear ratios
Rube Goldberg Device/The Incredible Machine - Create a complex device to perform a simple task.

Other miniLabs
 

What is your power output when you climb the stairs? (Science Spectrum p. 287)

A Simple Inclined Plane (Science Spectrum p. 294)

How do pulleys make work easier?

Materials:
two 3-foot lengths of PVC pipe (or similar); rope

Procedure:

  1. Working in groups of three, tie one end of a rope to a piece of PVC pipe or a broomstick handle. Wrap the other end around another piece of pipe once (see Figure A below).
  2. Two of the group members should each hold one pipe horizontally in their hands, with the pipes about 30 cm apart. The third person should grasp the free end of the rope and slowly try to pull the pipes together while the others try to hold the pipes firmly in place.
  3. Wrap the rope again around the first pipe (B). What happens now when the third person tries to pull the pipes together?
  4. Wrap the rope one or two more times across the pipes (C) and repeat the experiment.
Analysis:
  1. How is this similar to a pulley system? What increases the mechanical advantage of these pipe pulleys?
  2. Does this machine multiply the energy of the person pulling? Why or why not?
Can you measure the power of a toy car?

Materials:
inclined plane board, stopwatch, meterstick, spring scale, and wind-up or battery powered car

Procedure:

  1. Wind up a toy car and place it at the bottom of an inclined plane.
  2. Experiment to adjust the angle of the inclined plane (using books to stack under a board) so the car will reach the top at the slowest speed possible.
  3. Measure the time in seconds for the car to travel to the top of the plane.
  4. Measure the weight of the car in newtons using a spring scale.
  5. Measure the height of the inclined plane in meters. Be sure to measure from the floor or the tabletop straight up to the top of the inclined plane.
Analysis:
  1. Use weight (force) and height (distance) to calculate the work done in joules.
  2. What is the power of your toy car? Divide your work (joules) by the time (seconds) to get power (Watts.)
  3. What could you do to increase the power of the car as it travels up the same inclined plane?

Don't forget the internet based stuff as well: scavenger hunt, website evaluation, topic research, and STS articles. These are all described in the Free Exploration Procedures page.

Grading (maximum grade is variable based on number of FE days)