Activity 2: One on top of the other. Off together, Then apart. Stick a new 10-cm strip of Scotch tape with a handle to the lab table. Label the strip with a "b" for a bottom strip. Now, place a second new strip with a handle on top of the first strip. Label the handle on this strip with a "t" for the top strip. Rub the strips so they make good contact with the table and with each other. Quickly pull the bottom strip off the table and then pull the two strips apart and bring their non-sticky sides near each other. Does it matter which side of the strips face each other? Hypothesis: Observation: Conclusion: How does the distance between the strips affect what happens? Hypothesis: Observation: Conclusion:Activity 3: Place your "b" strip on the lab table. Place your "t" strip on top of the "b" strip (as you did in activity 2). Rub the strips so they make good contact with the table and with each other. Now prepare a new strip of tape (separate from your "t" and "b" tapes) and place in on the lab table away from the other strips. Rub the strip so it also makes good contact with the lab table. Quickly pull the strip labeled "b" off the table and then pull the "t" strip apart from the 'b" strip. Have you or your partner hold the two pieces of tape away from each other. Quickly pull off the third strip of tape and bring it near the b-strip and the t-strip. Which strips will be attracted? Which strips will repel? Hypothesis: Observation: Conclusion: Summary At this point you should be able to summarize the following outcomes of your investigations so that another student could understand your summaries. 1). In this activity, when do you think an object develops static electric charge? What evidence can you give to support your idea? 2 ) . How many types of electric charge are there? What evidence can you give for your conclusion? 3 ) . When a single piece of tape is pulled from the desktop, does it have the same charge as the top or bottom piece of tape in the combo set up? Why do you think so?1. Introduction Twenty-five hundred years ago, the Greek philosopher Thales found that when he rubbed amber, the hardened sap from a tree, it attracted light objects. A mere twenty-four hundred years later in the latter part of the nineteenth century, systematic investigations led to the formulation of a conceptual model of electricity that now allows us to understand Thales' experiment. During this lab, we will develop our own conceptual model for electricity by analyzing a series of simple experiments. 11. Electric charge and electric force You have all heard about electric charge. Well, for now, please forget EVERYTHING you have heard. For the rest of this lab, you are only to write comments and make statements that are supported by the observations and analysis of the experiments that follow. IF YOU DO NOT SEE IT, DO NOT SAY IT! In this section, the goal is to develop a meaning for the property of matter that is called electric charge. In these activities keep the tapes, except for the handles, away from your hands. Activity 1: Side by side. Remove two 10-cm long pieces Handle of regular clear tape from a roll of tape. Fold the ends of the tape over to make handles (see the sketch at the right). Press the sticky sides of the tape to the top of the lab table and rub them so that they make good contact with the table. Then, quickly pull the strips off the surface and bring the Sticky side non-sticky sides of the tape near each other. Record your observations. Hypothesis: Observation: Conclusion: Does it matter which side of the strips face each other? How does the distance between the strips affect what happens