Im trying to get my arms around the differences of using a constant current motor driver with current limiting resistors or a current sensing resistor setup with the SLA7062M. Questions to follow.

My motor for the sake of arguement and numbers is 5V @ 1amp. with a 30V power supply.

To construct a constant current board with current limiting resistors I calculate the resistor value as follows:
(30-5) / 1 = 25 I should use a 25 ohm resistor

To calculate resistor power, I calculate current squared multiplied by resistor value

1*25=25 ....so my 25 ohm resistor should be rated at 25 watts.

Am I out of whack here ??? Is this the formula to use???

Lets say I want to use current sensing resistor in the SLA7062M

href="http://www.pminmo.com/SLA7062/DIYSLA7062schematic.pdf"

I have used a formula that makes little sense and have difficulty in finding the basis for the 1.25 value.

Current sensing resistor calculated using 1.25/Amps out=ohms

So in my case 1.25/1=1.25 ohm resistor

Question: can I calculate power as in the previous example using current squared*resistor .
The example in the link shows two resistors in paralell (10,11) (19,20) so I expect the heat generated should be disappated over a couple of ? watt resistors.

Any help or assistance is appreciated.
Thanks in advance,
Whitney