Introduction to activity: This activity comes at the end of the unit that also has the example elicitation activity What happens with two bulbs? and the example development activity What effects do bulbs have on the flow of electricity in circuits?. This activity lets students apply their newly developed knowledge to some common situations.

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CE Activity II - A2: Christmas Tree Lights

Name: Group: Class Period:

	1. Imagine the circuit shown below.
	Predict what would happen to the brightness of the other bulbs in the circuit if the second bulb (B) were to burn out (so no electricity could flow through it), as shown in the diagram below. Double-click the picture to make your prediction.
	Explain your reasoning. What consensus ideas about the flow of electricity in parallel circuits justify your predictions?
	2. Now imagine the circuit shown below.
	Predict what would happen to the brightness of the other bulbs in the circuit if the second bulb (B) were to burn out (so no electricity could flow through it), as shown in the diagram below. Use the pictures below to represent your predictions.
	Explain your reasoning. What consensus ideas about the flow of electricity in series circuits justify your predictions?
	3. Test your predictions. Build each circuit, then remove bulb B. Were your predictions correct? If not, cross out the previous predictions and write in the correct information.
	4. Which arrangement do you think would work better for a string of Christmas tree lights? Explain your reasoning.