Coulumbs Law Lab Report Essay Example

Coulumbs Law Lab Report Paper This relationship is described by the following equation: Equation 1: In this equation, and are the charges on point charges 1 and 2 and r is the distance between the two charges. The direction of the force in this special case is always along a straight line drawn between the two charges. Additionally, it is important to note that charge is conserved; it can be moved but cannot be created or destroyed. Specifically, in this lab, we will move the charges around to setup a test of Coulombs law on a simple electroscope. As mentioned above, he experiment will be split into two parts, first measuring the force as a function of distance and then we will look at how the magnitude and sign of the charges affects the force. Lastly, we will use Equation 1 above to determine the amount of charge (in Coulombs) that we can generate with static electricity. 3. Experimental Setup The apparatus used in this experiment included: an electroscope chamber with suspended sphere and top cover, 2 guide blocks with spheres, cotton and wool squares, plastic rods, and a white vinyl strip. It is crudely drawn below. Figure 1 Electroscope Setup 4. Reoccurred Part 1 Charging a Sphere 1. Began by removing the right side guide block and setting it aside. 2. Inductively charged the sphere attached to the left side guide block by doing the following: a. Rubbed the wool square on the vinyl strip to transfer charge to the strip b. Brought the sphere on the guide block near to the charged strip but do not touch them together. Wi th the sphere close to the strip, I touched the sphere with my finger and then removed my finger. C. After the finger was removed from the sphere, I pulled the sphere away from the charged strip. The sphere on the guide block was then charged. Recharged the sphere again for the next part 4. Slowly slid the guide block with the charged sphere into the left side of the chamber and carefully observed the two spheres as they approached each other and just before they touch. Recorded observations. Part 2 Dependence of Force on Distance 1 . Now we wanted to add charge to the suspended sphere by charging our guide block sphere as before and then sliding it into the chamber until the two spheres touch. 2. When the two spheres touch, the charge becomes equally distributed among them. We repeated this charge transfer and kept increasing the charge n the suspended sphere. We will write a custom essay sample on Coulumbs Law Lab Report specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on Coulumbs Law Lab Report specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on Coulumbs Law Lab Report specifically for you FOR ONLY $16.38 $13.9/page Hire Writer Repeated this charging process until we had sufficient repulsive force to cause a separation of at least 1 CM to 2 CM. 3. Measured the displacement of the suspended sphere from equilibrium d for several different separation distances r. Took 5 different data points spread out over as wide a range as possible. Part 3 Dependence of Force on Charge 1 . Recharge the spheres, and after the two spheres have shared their charge, position the left guide block sphere such that you have a large displacement. Record the separation of the two charges r and the distance d. This is the first ATA point 2. Reduced the charge on the left guide sphere by half. To do this, grab the unused right guide block sphere and ground it using your finger, then remove your finger and touch the two spheres together. They now each have half the initial charge. 3. Now reposition the left guide guide block sphere to the previous value of r and record the new value of d. 4. Repeat this process two more times with 1/4 and 1/8 the original charge. 5. Experimental Results Part 2 Fee Calculation: Graph 1 Force vs Sphere Separation Graph 2- Force vs 1/raw Graph 3 Log of Force vs Log of 1/raw Part 3 Graph 4- Fee/Of vs Q/q Charge calculation 6. Questions part 1. A. What would happen if in step 2-c, you remove the charged strip from the vicinity of the sphere before your remove your finger from the sphere? B. What we have just done is charging by induction. In your own words describe what is happening in panels a through e in figure 2. C. The gray spheres are Styrofoam with a conductive coating. Why do we need the spheres to be conducting? D. Does the suspended force experience a force? Can you explain why the suspended sphere would experience a force even though it has no net charge? Doesnt this contradict Coulombs Law which says that you need two charged objects to have a force? E. Notice in the left panel of figure 3 that the size of the spheres is important the unlike charges are much closer to the charged sphere than the like charges. What is the consequence of this? Part 2- a. Plot a graph of the force as a function of the separation of the two spheres. Comment on the general trend of the data: does it look as you would expect? Why or why not? B. Is the graph linear? What would a linear dependence between Fix and 1/raw tell you? What does the slope of this plot represent physically?