Sacramento Charging Objects Lab Report-California State University .
Name:____________________________ Lab 1 Lab 1 – Electrostatics Report The lab is done according to the lab manual. The experiments are found at 5b lab Youtube, Lab 1 playlist. Watch and fill in the work sheet as you go. 1.4.1 Charging Objects Fill in the figures below. Draw showing where the gold foil is and where the net positive and negative charges are located at each time. 1a. The rod has a negative charge to start: 2a. The rod has a positive charge to start: 2 1b and 2b. How was the relationship between the Coulomb force and distance demonstrated? 3. a. Describe the way like charges were seen to repel. b. Describe the way opposite charges were seen to attract. c. Why were changes in direction included in the video? What does it demonstrate? 4. a. Draw to fill in the figures below showing where the gold foil is and where the net positive and negative charges are located at each time. 3 b. What charge is left on the electroscope? c. Explain how the electroscope can be charged without touching the charged rod to it. d. What will happen to the gold leaf if the positively charged rod were brought close to the electroscope while still charged? 1.4.2 Discharging 5. a. What was the charge put on the electroscope? b. What happened to the foil when the electroscope was touched to the pipe? c. Why did this happen? How is this different from using your finger? 6. a. What was the charge put on the electroscope? b. What happened to the foil when a lit match came close to the sphere? c. Why did this happen? 4 1.4.3 The Van de Graaff Generator 7. a. What was the charge put on the electroscope? b. Using words and charge diagrams, what would happen to the electroscope if a positive charge were brought near c. Using words and charge diagrams, what would happen to the electroscope if a negaative charge were brought near d. What happened to the gold foil when the proof plate was brought near? e. What is the charge on the proof plate and therefore on the Van de Graaff Generator? 5 1.4.4 Polarization 8. a. What is the charge on the rod? b. What happens when the rod is brought near the paper bits? c. Draw to show the charge distribution on the rod and the paper when they are close together: d. What would happen if the rod had the opposite charge? Would the paper attract or repel from the rod? 9. a. What is the charge on the rod? b. What happens when the rod is brought near the stream of water? c. What about the water molecules allows for this to happen? d. Draw in a few (abnormally large) water molecules. Show the charge distribution on the rod and the water molecules. 6 e. What would happen if the rod had the opposite charge? Would the water attract or repel from the rod? 1.4.5 Repulsion & Distance 10 a. negative rod marker ● distance angle (cm) (degrees) Positive rod marker × distance angle (cm) (degrees) b. Graph your data on the same plot using Excel and insert the graph here. Use Appendix C to guide you. There will not be a trendline. c. How does the behavior of the electroscope demonstrate Coulomb’s Law? d. Which rod had a larger amount of charge on it? How can you tell? 7 8
