Potential Energy

`LaToya Bennett                 Robert H. Lawrence                               9928 S. Crandon                               Chicago IL 60617                               (312) 535-6320Objective:The main objective of this mini teach is to introduce the concept of potential energy.  The students will recognize that potential energy is the ability to do work.  The students will identify the two factors that effect potential energy.The following activities will demonstrate the effect of height and weight on potential energy.  The activities are designed for the intermediate level.Materials Needed:weights             wooden blocks        tennis ball       rubber bandsnails               empty spools         meter stick hammer              wooden matches       string flat empty can      paper clips          ruler with center groovelarge rock          scotch tape          scissorspebble              buttons              books of various widthsStrategy:Activity - How does the weight of an object effect its gravitational           potential energy.1  Lift the pebble and the stone from the floor to the table.2  Place the flat can on it's side on floor near the table.3  Predict what will happen the pebble is pushed off the table and hits the can.4  Predict what will happen when the large stone is pushed off the table and    hits the can.Activity - The effect height has on the energy of an moving object.1  Cut an 1 in. square section in the top of a paper cup.2  Place the cup over the ruler.  The end of the ruler should touch the back of    the cup.3  Raise the opposite end of the ruler and rest it on the pencil. 4  Place the marble in the center groove at the ruler's highest end.5  Release the marble and observe.6  Repeat the steps above substituting books of various widths for the pencil.Activity - The effect weight has on potential energy1  Attach the string to handle of the pail.2  Secure the opposite end of the string to the edge of the table. The string    needs to be long enough to allow the pail to swing about one inch above the    floor.3  Place the paper on the floor under the hanging pail.4  Position the wooden block on floor in front of the pail.5  Pull the pail back and allow it to swing into the block.  Mark the position     that the block has moved to on the paper.6  Repeat the steps above adding large pieces of clay to add weight to the    bucket. Activity - The effect weight has on potential energy1  Cut a 2 inch square section in the top of a paper cup.2  Place the cup over the ruler.  The end of the ruler should touch the back of   the cup. 3  Raise the opposite end of the ruler and rest it on the book.4  Place the small marble in the center groove at the ruler's highest end.5  Release the marble and observe.6  Repeat the steps above substituting the large marble.Activity - Height and potential energy1  Position the 50 gram weight directly over the first nail.2  Lift the 50 gram weight to six inches as marked on the wooden bar.3  Release the weight and observe.4  Repeat the steps above raising the weight to 8 inches, 10 inches and 12    inches * If the first nail is damaged replace.Activity - Weight and potential energy1  Position the 20 gram weight directly over the first nail.2  Lift the 20 gram weight to the top of the wooden bar.3  Release the weight and observe.4  Repeat the steps above substituting various weights.   * If the first nail is damaged replace.As a closing activity the student can make a motorized spool.  This allows thestudent a hands, on at home, activity.  The students will construct the spool and answer a series of questions.  This also serves an evaluative tool. Activity - The motorized spool 1 Loop the rubber band through two of the holes in the button. 2 Make a small hole in the end of the paper clip and use it to pull the rubber    band through the hole in the spool. 3 Hold the rubber band in place in the spool by inserting a short length of a    Q-tip or a piece of the wooden match through the ends of the band.  Use    small pieces of tape to hold the stick in place. 4 Insert a Q-tip or match through the other end of the rubber band, the head of    the match or one end of the Q-tip near the hole, and the other end extending    out beyond the edge of the spool. 5 Using the long end of the stick, wind the rubber band 5 times.  Place it on    it's side on a table and let it go.  Observe the result. 6 Explain what happened to the spool when it was placed on the table?  7 Why did you have to wind the elastic band? 8 Explain where the energy came from to drive the spool. 9 Wind the spool again 5 times and using the ruler measure how it travels.10 Predict what will happen if you wind the band 10 times.  Test your prediction   by winding the band 10 times and letting it go on the table.  Describe the    result of your prediction.11 Experiment with your motorized spool by measuring the distance it travels    when wound 10, 15, 20 times.  Does the spool go twice as far with 20 turns as    it did with 10 turns?  Explain why it did or did not.12 Wind the rubber band 10 times and hold the stick in place with a piece of    tape.  Put the spool away until the next day.13 After storing the spool overnight remove the tape and release the spool on    the table.  How far does it go now?14 How well did the rubber band store energy overnight?The students will enjoy reporting their results the next day in class.Each of the activities are designed to show increased height and or increased weight will increase potential energy.`