Magnets & Electricity
Investigation 1: The Force
Part 3
Breaking the Force
Students use a balance and large washers to measure the force of attraction between two magnets. They systematically investigate what happens to the force of attraction as the distance between the two magnets increases. Students graph their results.
3. Lesson set up and Management
1.3.1 Define forces in terms of strength and direction.
2.1.2 Plan and conduct simple investigations, using appropriate tools, measures and safety rules.
2.1.3 Use data to construct reasonable explanations.
2.1.5 Record and report observations, explanations and conclusions using visual oral, written, and mathematical expression.
3.1.2 Propose, design and test a solution to a problem.
3.1.3 Evaluate how well a design or product solves a problem.
1. The greater the distance between two magnets, the less the magnetic force.
2. A force is a push or pull.
3. Lesson set up and Management
Materials:
1. You can either make a transparency of the graph on Student Sheet No. 5 or run off copies for students. Students can also create their own graphs.
2. Show how to set up balances, and let them explore before beginning the lesson. PLAY TIME!
3. After everything is set up and the kids have had time to explore the balance, ask the question "How many washers does it take before the magnets break the force?" Let them explore for 10 minutes or so before talking about standard measuring.
4. When beginning the standard investigation, make sure that all groups are using the same variables.
PLAY TIME! Let the kids explore with the balances before starting the standard investigation. |
Students use the same variables as other groups to carefully place the washers into the cups. |
Student Management:
1. Keep all materials at the station at which they are working. Don't let them carry the materials around. Let the students wander and explore.
2. Keep an eye on the child who may want to test the items near the caution signs.
3. Make sure everyone in the group gets a turn. Some students will tell their partners that they are doing the experiment wrong just so they can place the washers in the cup themselves.
4. Keep Moving! If you are constantly moving, it will keep everyone on task.
5. Make sure everyone does his or her own graph.
1. You can lengthen or shorten the time on any lesson.
2. Use Pages 2 & 3 to help guide further inquiry at the end of every part.
3. Give students time to discuss their observations with each other.
4. Give journal reflection time.
5. Keep word banks and content inquiry charts up so students can see and have more time to copy later, if needed. It's nice if you can keep them up all the time and just add to them as you go.
Writing Support:
1. Reflective journaling on the day's lesson. Write a sentence prompt for those students have difficulties starting such as, "I learned that the magnetic force gets __(stronger, weaker)____ when ________________________."
2. Start and finish each lesson with a KWLQ chart. ("What do I know?", "What do I want to know?", "What have I learned?" and "Are there any more questions to investigate?")
3. Have students write all word banks and inquiries in their journals.
Reading Support:
1. Check the Resources section of the teacher's guide for more reading suggestions or the literature link on this site.