3. The bulbs in the circuit at right are identical and the battery is ideal. a....

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3. The bulbs in the circuit at right are identical and the battery is ideal. a. Consider the circuit as shown. i. Rank bulbs A, B, and C according to brightness, from brightest to dimmest. Explain how you determined your answer. ii. Rank the voltages across the bulbs, in order from greatest to smallest. Explain. iii. Write an equation that relates the voltage across bulbs A and B to the battery voltage. iv. Is the voltage across bulb A greater than, less than, or equal to one half the battery voltage? Explain your reasoning. b. A student cuts the wire between bulbs A and C as shown. i. Rank bulbs A, B, and C according of brightness, from brightest to dimmest. Explain how you determined your answer. ii. Rank the voltages across the bulbs, from greatest to smallest. Explain. BO CO iii. Write an equation that relates the voltage across bulbs A and B to the battery voltage. iv. Is the voltage across bulb A greater than, less than, or equal to one half the battery voltage? Explain your reasoning. c. Consider the following discussion between two students regarding the change in the circuit when the wire in the circuit is cut (part b); Student 1: "I think that bulb B will get brighter. Bulb B used to share the current with bulb C, but now it gets all the current. So bulb B will get brighter." Student 2: "I don't think so. Now there aren't as many paths for the current, so the resistance in the circuit has increased. Since the resistance in the circuit has gone up, the current in the circuit decreases. Bulb B will get dimmer." i. Is student 1 correct? Why or why not? ii. Is student 2 correct? Why or why not? iii. Use what you have learned about voltage to determine whether bulb B will become brighter, become dimmer, or stay the same brightness when the wire is cut. Explain how you determined your answer. 3. The bulbs in the circuit at right are identical and the battery is ideal. a. Consider the circuit as shown. i. Rank bulbs A, B, and C according to brightness, from brightest to dimmest. Explain how you determined your answer. ii. Rank the voltages across the bulbs, in order from greatest to smallest. Explain. iii. Write an equation that relates the voltage across bulbs A and B to the battery voltage. iv. Is the voltage across bulb A greater than, less than, or equal to one half the battery voltage? Explain your reasoning. b. A student cuts the wire between bulbs A and C as shown. i. Rank bulbs A, B, and C according of brightness, from brightest to dimmest. Explain how you determined your answer. ii. Rank the voltages across the bulbs, from greatest to smallest. Explain. BO CO iii. Write an equation that relates the voltage across bulbs A and B to the battery voltage. iv. Is the voltage across bulb A greater than, less than, or equal to one half the battery voltage? Explain your reasoning. c. Consider the following discussion between two students regarding the change in the circuit when the wire in the circuit is cut (part b); Student 1: "I think that bulb B will get brighter. Bulb B used to share the current with bulb C, but now it gets all the current. So bulb B will get brighter." Student 2: "I don't think so. Now there aren't as many paths for the current, so the resistance in the circuit has increased. Since the resistance in the circuit has gone up, the current in the circuit decreases. Bulb B will get dimmer." i. Is student 1 correct? Why or why not? ii. Is student 2 correct? Why or why not? iii. Use what you have learned about voltage to determine whether bulb B will become brighter, become dimmer, or stay the same brightness when the wire is cut. Explain how you determined your answer.