Learning Objectives

--state that a current is a rate of flow of charge measured in amperes

--distinguish between conventional current and electron flow

--recall and apply the relationship charge = current x time time i.e. * Q = It = ne to new situations or to solve related problems

-- define electromotive force (e.m.f.) as the work done by a source in driving a unit charge around a complete circuit

-- calculate the total e.m.f. where several sources are arranged in series

--state that the e.m.f. of a source and the potential difference across a circuit component is measured in volts

--define the p.d. across a component in a circuit as the work done to drive a unit charge through the component

--*distinguish between e.m.f. and p.d. in terms of energy considerations

--*recall and solve problems using the equation V = W/Q

-- define resistance of a component as the ratio of potential difference across it to the current flowing through it

-- apply the relationship R= V/I to new situations or to solve related problems

--describe an experiment to determine resistance using a voltmeter and an ammeter and make the necessary calculations

-- recall and apply the formulae for the effective resistance of a number of resistors in series and in parallel to new situations or to solve related problems

--recall and apply the relationship of the proportionality between resistance and length and the cross-sectional area of a wire to new situations or to solve related problems

--state Ohm’s law

--describe the effect of temperature increase on the resistance of a metallic conductor

--sketch and interpret the V-I characteristic graph for metallic conductor at constant temperature, a filament lamp and for a semiconductor diode

-- show an understanding of the use of a diode as a rectifier

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What is current electricity? What is the connection of this to all the charges in the topic on electrostatics?

Electric Current

http://www.physicsclassroom.com/class/circuits/u9l2c.cfm

http://www.launc.tased.edu.au/online/sciences/PhysSci/done/electric/introele/Ielectr.htm

http://www.launc.tased.edu.au/online/sciences/PhysSci/done/electric/charge/Charge.htm

Electric Potential Difference

http://www.physicsclassroom.com/class/circuits/u9l1c.cfm

http://www.launc.tased.edu.au/online/sciences/PhysSci/done/electric/energy/Voltage.htm

Resistance

Explore the follow simulation to understand the factors that affect the resistance of a resisitor.

http://www.physicsclassroom.com/class/circuits/u9l3b.cfm

http://www.launc.tased.edu.au/online/sciences/PhysSci/done/electric/resistnc/Resistance.htm

http://www.bbc.co.uk/scotland/learning/bitesize/standard/physics/using_electricity/resistance_rev1.shtml

Activity on resistance http://www.bbc.co.uk/scotland/learning/bitesize/standard/physics/using_electricity/resistance_activity.shtml

Ohm's law

Colour codes for resistors

More indepth explanation on current, resistance and power (For those who will be interested)

http://www.montereyinstitute.org/courses/AP%20Physics%20B%20II/course%20files/multimedia/lesson35/lessonp.html

Alternating current

http://www.school-for-champions.com/science/ac.htm

http://vle.hci.edu.sg/physics/A-level%20Absorb%20Physics/units/020104.html