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 decrease▼because they are inversely proportional. (▲▼)

Likewise;
If  I (amps) decreases ▼then  E (volts) will decrease▼because they are directly proportional. (▼▼) 
If  I  decreases ▼then  R (resistance) will increase▲because 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 = I 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

    E ²                                                

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

    E ²                                              E ²

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

    E ²                                             E 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