1. E & M Road Races

2. Complete the following statements about charge interaction: 1.Like charges ________ and opposite charges __________. 2.When a charged object comes near a neutral object, what will happen? 3.When a negative object is held near a metal sphere, and the sphere is grounded, the sphere receives a __________ charge. 4.The description of charging in #3 is called ___________. Round 1

3. Complete the following statements about charge interaction: 1.1. Objects A receives a positive charge by rubbing against object B. What is the charge on object B? 2.What sort of charge actually moves along a conductor? 3.An object that holds onto its electrons very tightly is known as a ______________. 4.A negative vinyl strip is brought near but does not touch a conductor, what is the charge at the far end of the conductor? Round 2

4. 1.What happens to the force between two charges that are moved three times as far apart? 2. /3. What happens to the force between two charged conductors if the charge on both conductors are doubled and the distance between them decreases by a factor of three The energy always flows from a __________ object to a ____________ object. 4. A positive strip touches the knob of the electroscope and then removed. What happens to the leaves when it is removed? Round 3

5. 1. What direction does the field lines take with respect to positive and negative charges? 2. Draw the electric field lines that would surround a + Q charge. 3. Draw the electric field lines that would surround a – Q charge. 4. Draw the electric field lines that would surround a +Q and -3 Q charge that are near each other. Round 4

6. Round 5 1. What is the device used to measure current and how is it placed in the circuit? 2. If a light goes out in a string of Christmas lights and the whole strand goes out. Those lights must be connected in _________. 3. A 500 W device is connected to a 100-V power source. What Current flows through it? 4. If a pathway is removed from a circuit, resistance of the circuit ___________ and the current ____________.

7. Consider all bulbs to be identical. 1. Which branch has a greater current going through it? Explain. 3. If bulb 3 is unscrewed, what happens to the other bulbs? 4. If bulb 1 is unscrewed, what happens to the other bulbs? 5. If bulb 1 is unscrewed, what happens to the current going through the battery? Round 6

8. Bulb 1 has three times the resistance of bulb 3. Bulb 2 has twice the resistance of bulb 3. 1.Which bulb has a greater current traveling through it? 2.Which bulb has the greater voltage difference across it? 3.What is the voltage difference across bulb 3? 4.If a wire is connected across bulb 3, what happens to the brightness of bulb 1? Round 7