1-5 Equations

Chapter 5 equations p. 168-259

Ohm’s law:

Current =voltage     

             Resistance     

I = V            labels are:   amperes = volts

  R                                             ohms

*Remember just like speed always wins, so do volts.-They are always on top!

A)What is the current if the voltage is 120 volts and resistance is 80 ohms?

120 volts/80 ohms= 1.5 amperes

First Version of the same equation are:

Voltage = Current(Resistance)

B)What is the voltage for 30 amperes and 20 ohms?

30(20)= 600 volts

Second Version of the same equation are:

Resistance= Voltage

                                 Current

C)What is the resistance if there are 240 volt and 160 amperes?

240 volts/160 amps= 1.5 ohms

Electric power= voltage( current)  or P= V (I)   The label is watts  or kilowatts.

EX. How much power will a toaster oven use at 240 volts and 80 amps?

Toaster oven= 240 volts X 80 amps=

19,200 watts  or /1000 =19.2 Kilowatts

Electric energy= watt-hours or E=P(t)

The label is watt-hours or kilowatt-hours

i.e.  What is the electrical energy used if the television uses 4800 watts each hour it runs, and it runs for 4 hours?

Electric energy =power X time

4800 watts X 4 hours = 19,200 watts-hours or 19.2 kilowatts-hours