Day 59End of Topic 7! Starting Topic 8.

What’s Due and When:HW Turn In: Next Class,

◦HW: Titled Day 54, Day 57, Day 59.◦So the HW is due

Formal Lab: Checked with partners today,◦In my hands: Next Class (6)

Miniquiz: Next class

Today: Last Day of Topic 7/First of Topic 81st bit of time: Finishing

lab/confirming with partnersGoal One: To begin to understand

a new physics idea that deals with Charges.

1st: Lab TalkFor about 10 minutes, with

partners make sure you are all going to be ready to base your grade off each other.

I will take questions…

So a bunch of new ideas are coming your way that still deal with charges

CurrentIn the wire at every point, a

bunch of charge is flowing every moment.

Current is the Flow of Charge through a conductor

GIVE THIS ½ A PAGE. 18 LINES NEEDED

Label every 2 lines…1 to 6.The last 4 lines will be Equations section

GIVE THIS ½ A PAGE. 18 LINES NEEDED

Example One:3x1014 electrons are pushed every

minute through a wire. How much current is that?

Example Two: You TryA person has 400 milliamps go though

their heart to start it up. It took 3 seconds, how much charge flowed?

VoltageA field creates a force in the wire.

Its like a difference in Potential (like a push) on the ends of the wire push charge through.

Charge flows from High Potential to Low Potential.

A difference in Potential causes currents to flow.

Back to the chart…

ResistanceDifferent wires can have different flows

There are 4 different properties that affect the resistance.

More resistance with the same potential difference means LESS current

Back to the chart…

River AnalogyElectric Idea River

Example

Ohms LawThe relationship between Electric

Potential, Resistance and Current

Example Three:A metal wire is connected between two

battery leads. In an hour, 3 coulumbs flowed. If the wire is 75 ohms,

A) How much electric potential is there on the wire?

Example Three:A metal wire is connected between two

battery leads. In an hour, 3 coulumbs flowed. If the wire is 75 ohms,

B) If the high lead is 3 volts, what is the low?

Example Four:Which of the following changes to a wire

will always bring about an increase in current?

A) Increase voltage and increase resistance

B) Decrease voltage and decrease resistance

C) Increase voltage and decrease resistance

D) Decrease voltage and increase resistance

Example Four:Which of the following changes to a wire

could bring about an increase in current?

A) Increase voltage and increase resistance

B) Decrease voltage and decrease resistance

C) Increase voltage and decrease resistance

D) Decrease voltage and increase resistance

Example Five: You TryAn outlet has two prongs, + (120 volts)

and – (0 volts). You place a 20Ω wire from the + prong to a 30 volt battery. The battery charges in 20 minutes. How much charge flowed?

And Now…Try it out on the HW