1.  ELECTRIC CURRENT  P. 516-518

2.  A battery is a device that converts stored chemical potential energy into electrical energy and is capable of providing a steady flow of current electricity.  Current electricity is the flow of charged particles along a conductor.

3.  electrical circuit - steady flow of charged particles along a closed loop.  A circuit contains:  a source of electrical energy, such as a battery  a conductor, such as a wire  a load that changes electrical energy into light, sound, heat, or motion.  (can have a switch but doesn’t have to have one for circuit to work)

5.  The amount of charge transferred per unit time is referred to as current.  When scientists first began studying circuits, they assumed that positive charges flowed through the wires in a circuit.  They called the flow of positive charges in a circuit conventional current.  Since unlike charges attract, conventional current is considered to flow from the positive terminal of a battery, around the circuit to the negative terminal.

7.  After scientists learned more about the structure of atoms, they concluded that current consists of free electrons, which are negatively charged.  During the operation of a circuit, the electrons move from the negative terminal of the battery to the positive terminal.  The movement of electrons in a circuit is called electron flow.  we will stay with the convention and use the term conventional current.

8.  http://education- portal.com/academy/lesson/what-is-electric- current-definition-unit-types.html http://education- portal.com/academy/lesson/what-is-electric- current-definition-unit-types.html  TVO  http://www.youtube.com/watch?v=YLeRbTlK kJY http://www.youtube.com/watch?v=YLeRbTlK kJY

9.  Current is represented by the symbol capital I, and is measured in amperes (A). Q Q

10. http://www.youtube.com/watch?v=9iKD7vu q-rY

12.  A battery provides a steady flow of current in one direction, known as direct current, or DC.  Strictly speaking, DC can fluctuate, but cannot change directions.  DC is used in all electrical equipment that requires an adapter when you plug it into a wall outlet or is powered by a battery.

13.  The movement of electrons in only one direction, protons do not move

14.  A wall socket provides alternating current.  Alternating current, or AC, changes direction periodically.  That is, the charges in the wire move back and forth over the same spot and do not actually move from one terminal to another.  This type of current is used in the wiring of your house.  http://www.pbs.org/wgbh/amex/edison/sfeature /acdc.html http://www.pbs.org/wgbh/amex/edison/sfeature /acdc.html

15.  http://www.youtube.com/watch?v=g17f9J1-r- k http://www.youtube.com/watch?v=g17f9J1-r- k  http://www.youtube.com/watch?v=xyQfrzBf nDU http://www.youtube.com/watch?v=xyQfrzBf nDU

16.  A battery delivers a charge of 9.00 C in 1.00 min of operation.  What amount of current is generated in mA? Q Q

17.  A device called an ammeter is used to measure current.  The ammeter is placed into the circuit (series) so that the current flows through it.  Since the current cannot bypass the meter, the meter measures the entire current.

19.  Calculate the amount of current through a wire that has 0.85C of electrons passing a point in 2.5 min.  Given: Q=t=  Required: I=? (A)  Analysis: convert time to seconds, solve for I  Calculate the amount of current through a wire that has 0.85C of electrons passing a point in 2.5 min.  Given: Q=t=  Required: I=? (A)  Analysis: convert time to seconds, solve for I

20.  Since charges have basically no room between them, if there is something that restricts the flow of current in one spot in the circuit, the effect is felt throughout the entire circuit.  Resistance is the degree to which the flow of current is opposed in a circuit.  A resistor is a device that resists or restricts the flow of current.

21.  As charges move through a resistor, the resistor removes energy from the charges and converts it to another type of energy.  The energy usually takes the form of heat.  For example, a light bulb is a resistor that converts the energy of the charges into heat and light.  Almost all components offer some resistance in a circuit, even if that is not their primary role.  We will assume that the resistance of a component is constant.

22.  Georg Ohm applied different voltages to a resistor and measured the corresponding current and voltage drop across it.  Ohm recorded and made a graph of his data

23.  The slope of this line is the resistance. Because the relationship between potential difference and current is linear, the resistance does not change.  Ohm wrote this relationship mathematically as: where R is the resistance in ohms (Ω), V is the potential difference in volts (V), and I is the current in amperes (A). This mathematical equation is known as Ohm’s law. Ohm’s law is often rewritten as:

24. Section 11.5 Calculating Battery Life A rechargeable AAA battery has a rating of 1260 mAh. How long could it produce a current of 328 mA? Use the data from the problem to fill in the Given information. Then, use the variables in the Given information to fill in the formula. Click the screen for hint. Given: I = Q = Required: ∆t Analysis: = = current charge (rating)

25. Section 11.5 Calculating Battery Life A rechargeable AAA battery has a rating of 1260 mAh. How long could it produce a current of 328 mA? Use the data from the problem to fill in the Given information. Then, use the variables in the Given information to fill in the formula. Click the screen for hint. Given: I = Q = Required: ∆t Analysis: = = Current charge (rating) 328mA 1260 mAh ∆t∆t ∆t∆t ∆t∆t Q Q Q I I I

26. Section 11.5 Calculating Battery Life A rechargeable AAA battery has a rating of 1260 mAh. How long could it produce a current of 328 mA? Use the data from the problem to complete the calculation. Then, complete the final statement. Solution: ∆t = ∆t = __________ h ∆t = ____ h ____ min Statement: The battery could produce a current of 328 mA for __________.

27. Section 11.5 Calculating Battery Life A rechargeable AAA battery has a rating of 1260 mAh. How long could it produce a current of 328 mA? Use the data from the problem to complete the calculation. Then, complete the final statement. Solution: ∆t = ∆t = __________ h ∆t = ____ h ____ min 1260 mAh 328 mA 3.84 350 Statement: The battery could produce a current of 328 mA for __________. 3 h 50 min

28.  P. 517 practice #1-2  P. 518 questions #1-4  http://www.youtube.com/watch?v=1xPjES- sHwg&feature=youtu.be http://www.youtube.com/watch?v=1xPjES- sHwg&feature=youtu.be