190 likes | 204 Vues
Test your knowledge of electric current and circuits with these interactive clicker activities. Explore the effects of adding light bulbs in series and parallel circuits.
E N D
Ch. 23 Electric Current Clicker Activities
Task • You will be shown four different arrangements of light bulbs connected to batteries with conducting wires. The arrangements will vary with their being between 0 and 4 light bulbs connected in series. Assume all pieces in the circuit behave perfectly. A voltmeter will be used to measure the potential difference between the terminals of the battery.
V1 V2 V3 V4
Rank the potential difference measured between the two battery terminals from the greatest to the least. If there are any ties indicate them. • V1 > V2 > V3 > V4 • V4 > V3 > V2 > V1 • V1 = V4 > V2 = V3 • V1 = V2 = V3 = V4 • Cannot be determined
What was the reason that you ranked them that way? • The more resistors, the more voltage the battery supplies • The more resistors the less voltage a battery supplies • The voltage is used by the first light bulb, then the next … • The bulbs on the end use up the voltage first • Ideal batteries always provide the same voltage
How confident are you about your answer? • I know I’m right • I’m pretty sure • Neutral • I’m mostly guessing • I’m completely guessing
Task – A student builds a series circuit with a battery and three identical light bulbs. She correctly determines that the circuit will draw .3 A. Between each circuit element she inserts an ammeter. Before closing the switch she predicts what the reading of each ammeter will be as shown in the next slide. What if anything is wrong with her prediction?
.3 A .2 A .1 A 0.0 A
What if anything is wrong with the predicted values of the ammeter readings? • Nothing the predictions are correct • The values are correct but the order of the readings should be reversed • The readings should all be the same • The readings should be greater on the outer ammeters • The readings should be greater in the middle
How confident are you about your answer? • I know I’m right • I’m pretty sure • Neutral • I’m mostly guessing • I’m completely guessing
Several Circuits will be modified by changing the number of light bulbs. Your task will be to predict and explain how adding the light bulbs will change the reading on the ammeter and the brightness of each bulb.
Consider the following circuit. An additional resistor will be added in series. Answer the following questions.
What will happen to the reading on the ammeter? • It will increase • It will decrease • It will remain the same • Some other answer
What was your reason? • The resistance went up so less current • More light bulbs so more current • The battery remains the same so no change • Some other answer
What will happen to the brightness of each light bulb when the third one is added? • It will remain the same. • It will increase • It will decrease • Some other answer
Consider the following circuit. A 3rd light bulb will be added in parallel. Answer the following questions.
What will happen to the reading on the ammeter? • It will increase • It will decrease • It will remain the same • Some other answer
What was your reason? • The resistance went up so less current • More light bulbs so more current • The battery remains the same so no change • Some other answer
What will happen to the brightness of each light bulb when the third one is added? • It will remain the same. • It will increase • It will decrease • Some other answer