Capacitors Rogelio Campa 6341 Inductive Lesson

Requirements Who was your audience? Who was your audience? –Teachers for 11 th grade Electronics class What concept did you want the students to learn? What concept did you want the students to learn? –What is a capacitor and how does it work How did you conduct the lesson How did you conduct the lesson –Opening hook As students walked in handed them two springs As students walked in handed them two springs Hand a number 1, 2, or 3 etc… Hand a number 1, 2, or 3 etc… Had them come up with a hypothesis Had them come up with a hypothesis Asked them to decide which one was a capacitor and why Asked them to decide which one was a capacitor and why –Lesson Explained what a capacitor is and how it works Explained what a capacitor is and how it works –Activity Group work set all 1, 2, 3… together Group work set all 1, 2, 3… together Create their own capacitor and see how it works Create their own capacitor and see how it works –Closing Importance of safety with electronics Importance of safety with electronics Clean-up Clean-up

Requirements Cont. What was the Student response – What was the Student response – –(Before) students wondered what the springs were for students wondered what the springs were for –(During) They were curious They were curious Kept them wondering what was next Kept them wondering what was next –(After) Understood their objective Understood their objective Wanted more Wanted more What did they learn? What did they learn? –Learned what a capacitor was and how it worked What will you do differently next time? What will you do differently next time? –Use a different spring (not a slinky)

Capacitors What is a capacitor? What is a capacitor? How do they work? How do they work? Safety? Safety?

Two Springs Spring 1Spring 2

First Attempt Spring 1 Spring 1 What do you think will happen What do you think will happen –Come up with a hypothesis Pull apart as much as you can Pull apart as much as you can While holding it let go of one side While holding it let go of one side Explain what happens Explain what happens

Second Attempt Here is spring 2 Here is spring 2 Pull apart as much as you can Pull apart as much as you can While holding it let go of one side While holding it let go of one side Explain what happens Explain what happens

What happened? Which one do you think is a capacitor? Which one do you think is a capacitor? Why? Why?

Symbol?

Capacitors Stores Energy like a battery. Stores Energy like a battery. Capacitance is the storage potential of a capacitor Capacitance is the storage potential of a capacitor Storage is measured in farads (energy) Storage is measured in farads (energy)

Construction Paper Construction Paper Activity 1 Foil Paper

Instructions Fold consturction paper hot dog style Fold consturction paper hot dog style Wrap one piece of foil around one strip of construction paper. Wrap one piece of foil around one strip of construction paper. –Make two pieces. Place between the construction paper Place between the construction paper –Make sure they don’t touch –You will get a slight shock if they do Once we have charged the capacitor Once we have charged the capacitor Take a nine volt battery and the wires Take a nine volt battery and the wires

Instructions Cont. Safety – Don’t touch the foiled ends Safety – Don’t touch the foiled ends –They hold a small electrical charge –Make sure that you are careful Take the end of the tester and touch one end of the capacitor Take the end of the tester and touch one end of the capacitor When ready touch the other end and explain what happens. When ready touch the other end and explain what happens. –What did you see? –What happened? Clean up! Clean up!

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