You will need to read the section on power, do the assigned problems so that you are an expert.

Also be able to derive the expressions for power from ohms law.

P = work/time = Vq/t = VI because I = q/tThen just substitute from R = V/I

You want to make about 4-6 whiteboard questions as these are not to difficult. Try to use all the formulas.

Powerpower = work

timeDerive all eqn using:V = W/qI = q/tR = V/I

P = IV = I2R = V2

R

P: Power in WI: Current in AmpsV: Voltage in VoltsR: Resistance in Ohms

Example 1: goes here

Example 2: goes here

Demo: power supply and heating element, motor and ammeter (I can do these for you?)

Whiteboards I think you should do 5 or 6 – try to use all three power equations

equally

1 | 2 | 3 | 4 | 5 | 6

A heating element draws 2.07 A from a 12.0 volt source. What is the power it consumes?

24.8 W

Given:P = IV = I2R = V2

RP = ??V = 12.0 VI = 2.07 AR (not given)

Use P = IVP = 24.84 = 24.8 W

W

Question goes here?

answer

Given:P = IV = I2R = V2

R R

P =V =I =R =

Use

Question goes here?

answer

Given:P = IV = I2R = V2

R R

P =V =I =R =

Use

Question goes here?

answer

Given:P = IV = I2R = V2

R R

P =V =I =R =

Use

Question goes here?

answer

Given:P = IV = I2R = V2

R R

P =V =I =R =

Use

Question goes here?

answer

Given:P = IV = I2R = V2

R R

P =V =I =R =

Use