Day 64 Topic 8: Charges and Circuits Electric Power, Costs and More.

Day 64Topic 8: Charges and Circuits

Electric Power, Costs and More

3rd QuarterLast HW: Do For Next Class (65) along

with this one (65). 2 Things Due! Considered covered

Next Class: Classwork occuring, MiniQuiz!2 More New Learning Days Left (Lab on 66)

Q3 Review Day 67 3/25, 3/26

Q3 Exam Day 68 3/27, 3/30

Brunch of Champions Day 69 3/31, 4/1

My Goals:1. The 4 things that affect

resistance: Knowing and applying

2. Using Power to find energy and costs

First Of All…You Do20 bulbs (each one is 20 ohms)

are connected so each has a potential difference of 30 v.

A) How much power do the bulbs give off?

First Of All…I Do20 bulbs (each one is 20 ohms)

are connected so each has a potential difference of 30 v.

B) In 10 minutes, how many joules are given off?

Power and ResistanceIn order to explore power, we

now need to discover the 4 things that affect resistance.

Grab a RESISTOR from me

With the wire in your hand…What physical things about that

wire can you change to make a different amount of flow occur?

The 4 things: Think of cars…Length:

Thickness:

Material:

Temp:

Ohmic Vs Non-OhmicIf a situation is Ohmic, the

resistance will not change if the voltage or current changes (i.e. temp don’t matter). V=IR works

If a situation is Non-Ohmic, then the resistance changes with different voltages or currents. Temp plays a role

Which one/ones are Ohmic?

Which one/ones show that the resistance is increasing?

Part Two: EnergyFrom our tables, Power is

Energy/Time.

Energy symbol is: measured in

To the table:

Lets try…

And You…