MS - PS2.B (A) - Electromagnetic Forces - FINAL (CLF 1/29/2014)

Module: Electromagnetic Forces

DCI: PS2.B (A) Electric and magnetic (electromagnetic) forces can be attractive or repulsive, and their sizes depend on the magnitudes of the charges, currents, or magnetic strengths involved and on the distances between the interacting objects.

PE: MS-PS2-3  Ask questions about data to determine the factors that affect the strength of electric and magnetic forces.

 [Clarification Statement: Examples of devices that use electric and magnetic forces could include electromagnets, electric motors, or generators. Examples of data could include the effect of the number of turns of wire on the strength of an electromagnet, or the effect of increasing the number or strength of magnets on the speed of an electric motor.] [Assessment Boundary: Assessment about questions that require quantitative answers is limited to proportional reasoning and algebraic thinking.]

The ideas in this standard are: 

- electric and magnetic forces can be attractive or repulsive

- the size of an electromagnetic forces depends on the magnitude of the charges, currents, or magnetic strengths involved AND the distance between the interacting objects 

So since the PE says for students to "ask questions" and we will be the ones asking the questions, we can do some sort of investigative design set-up and ask them to tell us what the students might be testing.  Or, we could provide data and ask them to make a conclusion based on the data. 

Possible Question Starters: 

"Students attached both ends of a long wire to the poles of a battery and wrapped the wire around a spoon.  In this arrangement, the spoon is able to pick up several small paperclips.  

If the students want the spoon to be able to pick up more paperclips, which of the following should they try doing?"

correct answer - increasing the number of times the wire wraps around the spoon

incorrect answer - using a spoon with a longer handle

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