**
It is expected that students will explain how electric current results from separation of charge and the movement of electrons.**

**Students who have fully met the prescribed learning outcome are able to:**

Distinguish between

- potential and kinetic energy

- static electricity and electric current

- conventional current and electron flow

Relate the charge on electrons to electron flow in a circuit (i.e.,

from negative to positive)

Define current in terms of the amount of electric charge that

passes a point in a given time interval

photo: lucky-frank@morguefile

**RESOURCE**

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PLANNING FOR ASSESSMENT /**ASSESSMENT STRATEGIES**

Review with students the definitions of force,

types of energy, and static charge. Ask students

“When an object has a static charge, where are

the charges positioned?” Discuss repulsion of

like charges. “What if you touch the charged

object or give the charge a path (wire) to

ground?” Discuss grounding ( more).

• Assess whether students’ answers to questions

show that they understand the difference between

kinetic and potential energy with respect to static

electric charges and electric current.

• Have students draw and label diagrams that

illustrate forces, energy, and charge (static and

moving). Verify accuracy.

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Explain that electrons flow as a result of

attractive and repulsive forces acting on them.

Briefly explain how voltage is a description of

the amount of energy of a charge (i.e., due to

the separation of charges). Ask, “How can

energy be given to a charge?” Demonstrate

and explain some different types of power

supplies, energy converters, and generators.

Then show students the symbols used in

circuit diagrams and how to measure voltage

of cells using a voltmeter.

Assess students’ understanding of energy

generation by considering how many different

ways of giving energy to a charge they can

identify (e.g., rubbing two materials, using a

chemical cell, a generator, thermocouples, piezoelectric

device, photo-electric cell).

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Have students use a voltmeter to measure the

voltage of cells connected in series and in

parallel.

Have students draw circuit diagrams to represent

their work with cells and voltmeters. Assess the

extent to which their diagrams

- show the correct arrangement of cells in series

and parallel

- use proper symbols for devices used

- include proper voltmeter readings (with

units)

- include conclusions about the differences in

voltage when cells are connected in series and

parallel

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Define current for students as a rate of chargeflow (the amount of electric charge that passes

a point in a given time interval). Explain that

historically (before the time of Coulomb),

people believed that positive charges flowed

through a wire (conventional current).

Compare this with the modern understanding

(flow of electrons).

• Instruct students in the correct use of an

ammeter.

Have students use an ammeter (lab) to measure total

current in a series circuit vs. a parallel circuit as

more devices (resistors, light bulbs) are added

(voltage is kept constant). Have them record

observations using circuit diagrams and draw

conclusions. Assess their work by considering

whether they have

- properly connected the ammeter

- obtained reasonable measurements

- drawn symbols correctly

- recognized how current changes when

devices are added in both series circuits

(current decreases) and parallel circuits

(current increases)

Consider using the Lab Report Performance Task

Definition and the Lab Report Scoring Rubric

provided at the end of the Classroom Model for

this grade.