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One of the major topics on the New York State Regents is electricity. Of course there are many subsections for this topic. Static electricity is usually where I begin this unit. One of the obstacles that I have faced is the expense of some of the standard equipment. A staple of the New York State Regents curriculum is the leaf electroscope. The typical square electroscope with glass windows can cost forty-five dollars each when purchased from the science supply companies. Ideally a teacher might have students work in groups of two. Therefore a class with twenty-four students would require twelve electroscopes. This would costfive hundred and forty dollars. If you have multiple teachers needing this equipment at the same time this can become extremely expensive.I have an inexpensive solution that the students seem to enjoy. Rather than using the “professional electroscopes”, my classes make their own electroscopes, which they can later bring home, and demonstrate, to their family members. (A big plus, because we all know that if someone is capable of explaining and demonstrating a phenomenon to others, they have probablyunderstood it themselves!) The materials required for this “make and take” are standard large paper clips (solid not notched), scotch tape, aluminum foil, and 5x8 index cards. Total cost; about four dollars for three classes. The steps for building the electroscope are as follows:1. Cut the index card lengthwise in half.2. Fold each of the two parts in half (perpendicular to the lines on the card).3. Fold a one-centimeter tab at one end of each of the two pieces.4. Attach the two pieces to each other by taping the tabbed end of one piece to the straight end of the other. Repeat for the other side. At this point you should have a square frame.5. Take a large paper clip and lay it down flat on your desk. Fold the small loop away from the larger loop at the point at which the wire ends so that the loops are perpendicular to each other, and both loops still exist.6. Using a pencil point (or any thin sharp object) poke a hole in the center of a side of the square frame (this will be the top of the electroscope)7. Feed the large end of the paper clip through the hole until the short loop rests flat on the index card. (You may need to unfold the paper clip to accomplish this.) Tape the short loop to the index card for stability.8. Using aluminum foil (Heavy duty foil works best) cut two strips approximately one centimeter by three and a half centimeters. These will be the vanes of the electroscope. At this point you have a leaf electroscope that will demonstrate static electric phenomenon. However a charged object is necessary. The standard lab requires an ebonite rod with fur. The rod becomes negatively charged when rubbed with the fur. An inexpensive substitute for this is apiece of Styrofoam rubbed on your hair or sweatshirt. (Balloons also work if latex allergies are not an issue).The vanes of the electroscope will clearly diverge. However when removing the charged Styrofoam from the paper clip the vanes quickly fall. I have found that taking a small amount of aluminum foil and compressing it into a ball to serve as a knob makes for a more robust electroscope. Simply attach it to the top of the paper clip. This will cause the vanes to stay diverged for a longer period of time when charged by conduction.In addition to the leaf electroscope the New York State curriculum includes pith ball electroscopes. Again, the cost of buying the “professional” pith ball kits is more expensive thanthe following alternative. What you will need is a can of aluminum paint, Styrofoam packing peanuts and thread. Before class spray the packing peanuts with the paint and allow them to dry. (This also works with out the paint if you so desire.) Tie the packing peanut to a length of threadso that the peanut hangs twelve to fifteen centimeters long. Place a textbook one-third off the edge of the desk and tape the end of the thread to the textbook. Again using the charged Styrofoam conduct the lab as if it were the “professional” equipment.It is obvious that having digital scales available to physics students make for more accurate data collection. In addition, labs can be modified to use these scales, not only to enhance the values taken, but also demonstrate physics phenomenon that might otherwise have to be explained rather than observed. Science supply catalogues list digital scales ranging from one hundred and sixty seven dollars to four hundred and twenty nine dollars depending on the capabilities of the scale. This is highly expensive considering that similar scales sell for twenty dollars in the Harbor Freight Catalogue. For the cost of one of the lower end scales in the science supply catalogues, you might purchase eight scales from Harbor Freight. However, whatmight one do with these scales once they have been purchased?A typical physics question asked of students involves stepping on a scale in an elevator. Students might be asked to consider the reading on the scale if the elevator accelerates upward ordownward, as compared to the baseline reading (before the elevator moves). As we all know, themass of an object does not change, however its weight is relative to gravity, or in this case, the rate of acceleration. You may have an elevator in your building to try this, however there are many things to consider. For example the elevator may move so slow that there may not be a noticeable, or sustained difference. In addition you may only be able to fit four to six people in the elevator making supervision of the class difficult.There is a way that you might demonstrate this in class. A simple modification to the “modified Atwood” apparatus can afford your class an “eyes on” opportunity to this phenomenon. Begin with a sturdy piece of cardboard (the thicker the better). Cut the cardboard into a square large enough for the scale to rest on. Punch four holes in the corners of the cardboard. Feed string through the top of one hole and run it diagonally (underneath) to the other hole. Repeat for the other two holes. The four ends of the string should be tied together so that you have the outline of a pyramid approximately thirty to fifty centimeters tall at the center (depending on the type of uprights and crossbars available to you) .Attach two pulleys, one on each corner of you desk. (You may want to use an upright


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