## Pages

### Triangle Charts

Triangle Charts

Another way to express Ohm's Law is with triangle charts like this one,

 E I  l  R

Meaning that,
If  I (amps) increases then E (volts) will increase because they are directly proportional. ()
If  I  increases then  R (resistance) will decreasebecause they are inversely proportional. ()

Likewise;
If  I (amps) decreases then  E (volts) will decreasebecause they are directly proportional. ()
If  I  decreases then  R (resistance) will increasebecause they are inversely proportional. ()

The triangle chart helps to physically see the multiplication or division formula by covering up one of the 3 variables
.
To find E cover it with your finger to reveal the formula I x R or E is equal to I times R.
To find I cover it and reveal that I is equal to E divided by R.
Cover R and find R is equal to E divided by I.
Notice that the horizontal separator line (the left to right line like the horizon) is either a
mathematical line of division or an equal sign. The vertical (up and down) separator line is either a multiplier or an equal sign. So, when you cover the E, the horizontal line becomes an equal sign creating the formula;
E = I x R but not; E divided by I x R

This single triangle chart above is one of 4. It displays only 3 of the 12 formulas.

#### ✦All 4 Triangle Charts✦

Here are the 4 separate triangle charts used to display all 12 of the Ohm's law formulas. Make a copy of them.
If you memorize these 4 triangle charts you will know all 12 formulas by covering up one variable as mentioned in the example above;

E
______

I   I   R

E
I \ R   reveals; (by covering the E)   E = x R
E                                                   E
I \ R   now hide the I and reveal;  I =   R
E                                                   E
I \ R   now hide the I and reveal;  R =  I

To get to the next chart, square the E and change I to P.

 E 2 P  l  R

2
P \ R   reveals  E2 P x R   or   E =  (PxR)

2                                              2
P \ R   cover the P and reveal;   =  R

2                                             2
P \ R   cover the R and reveal;   R =  P

To get to the next chart think "PIE"

P

I \ E

P                                                 P                   P
I \ E   reveals;   P = I x E   and  I =   E    and  E =   I

To get the next chart, square the I change E to R.

 P I2  l  R

P                                                        P                      P
I2 \ R    reveals;   P =  I2 x R   and   I2  =  R      and  R  =   I2