1. oneone GTE-12A Objective: To explore electric circuits in order to explain how they relate to magnetic fields. Energy Note: Are electricity and magnetism related ? Drill: 1. Get a new lab from the SET. 2. Read the activity. 3. Imagine completing the activity. ELECTROMAGNETS

2. oneone GTE-12A Activity 1: Exploring a Compass 1. Take the magnet and the compass. 2. Hold them about 30 cm apart. 3. Slowly move the magnet closer to the magnet. 4. Record your observations. Repeat if necessary. ELECTROMAGNETS

3. oneone GTE-12A 1. Construct a simple circuit using the provided materials. (Just a 2 cells wired to a switch) Leave the switch open. 2. Place the compass near the circuit. Record your observations in the left half of Figure 1, “Compass Observations.” (Draw the compass needle.) N S EW ELECTROMAGNETS

4. oneone GTE-12A 3. Close the switch. Record your observations in the right half of Figure 1, “Compass Observations.” N S EW ELECTROMAGNETS

5. oneone GTE-12A Explain the movement of the compass needle after the wire was connected to the circuit. Use your observations and prior knowledge about the effects of magnets on compass needles to support your answer. Compasses react to magnetic fields. The compass needle moved when the circuit was closed. Therefore, the circuit must produce a magnetic field. ELECTROMAGNETS

6. oneone GTE-12A The observations you just made represent one of the biggest blunders in the history of science. However, this blunder has revolutionized technology and enabled scientists to develop devices that convert electrical energy into mechanical energy. ELECTROMAGNETS

7. oneone GTE-12A READ and NOTATE the passage, “OERSTED’S SURPRISE”. What problem did Hans Oersted have? ELECTROMAGNETS

8. oneone GTE-12A Why does a compass needle move when it is placed next to an electrical circuit? Use information from the reading to support your response. A compass needle moves when placed next to an electrical circuit, because an electrical circuit PRODUCES A MAGNETIC FIELD. ELECTROMAGNETS

9. oneone GTE-12A Homework: Electromagnets Lab – Pre-reading and Hypothesis ELECTROMAGNETS

10. oneone GTE-12A Objective: To explore electric circuits in order to explain how they relate to magnetic fields. Energy Note: Are electricity and magnetism related ? Drill: 1. Take out both your lab and yesterday’s Lesson Sheet. 2. Reread the passage that tells about the blunder. What if this happened to you? 3. Wait for directions. ELECTROMAGNETS DAY 2

11. oneone GTE-12A Problem Question: How does the number of coils of wire wrapped around a core affect the strength of the electromagnet? Independent Variable: # of coils wrapped around the core. Dependent Variable: strength of the electromagnet. ELECTROMAGNETS

12. oneone EEM-12A Materials: iron nail electrical wire (1 m) Switch paper clips (1 box) two alligator wires 2 D-cells w/ holders ELECTROMAGNETS

13. oneone EEM-12A Hypothesis: (Write in “If…,then…, because…” format.) If the number of coils wrapped around the core increases, Then the strength of the electromagnet will…, because… ELECTROMAGNETS

14. oneone GTE-12A 1.Strip the plastic covering from the two ends of the wire. (This may already be done for you.) 2.Make ten tight wraps around the middle of the nail, starting about 5 centimeters from the end of the wire. 3.Place the D cells in the battery holders. Connect the cells together with a wire. 4.Attach one open terminal of a cell with a wire to a switch. Leave the switch open. 5.Attach one end of the wire to the switch and the other end of the wire to open terminal of the second cell. 6.Close the switch to operate. Caution: Do not leave the switch closed for more than fifteen seconds at a time. The wires may become very hot. ELECTROMAGNETS

15. oneone GTE12A 1.Place the paper clips in a small pile on the table. 2.Complete the circuit containing the electromagnet by closing the switch. 3.Place the tip of the electromagnet slowly into the pile of paper clips. 4.Remove the electromagnet from the pile. 5.Open the switch. Count the number of paper clips that adhered to the end of the electromagnet. 6.Record the data in the appropriate space in Chart 1, “Effect of the Number of Coils on Number of Paper Clips Lifted by the Electromagnet.” 7.Repeat steps A-F using electromagnets constructed with 20, 35, and 50 coils. ELECTROMAGNETS

16. oneone GTE-12A CHART 1 EFFECT OF THE NUMBER OF COILS ON THE NUMBER OF PAPER CLIPS LIFTED BY THE ELECTROMAGNET Number of CoilsNumber of paper Clips Lifted 10 20 35 50 ELECTROMAGNETS

17. oneone GTE-12A Conclusion Answer the lab question. Provide evidence from the lab to support your conclusion. ELECTROMAGNETS DAY 2

18. oneone GTE-12A Homework: Lab Analysis…Selected Questions #1, 5, & 6 ELECTROMAGNETS DAY 2

19. oneone GTE-12A Objective: To explore electric circuits in order to explain how they relate to magnetic fields. Energy Note: Are electricity and magnetism related ? Drill: 1. Take out your Activity Sheet, Lab, and Analysis. 2. Proofread your homework answers. 3. Wait for directions. ELECTROMAGNETS DAY 3

20. oneone EEM-12A RECAP and DEMO ELECTROMAGNETS DAY 3