V-drop question

[LeoRex]

I was thinking about voltage drops and the like and was curious.... let's say you have a fully charged battery in a mech, with some random 1 ohm rda.

Measuring the voltage across the rda posts, you get 3.8v... so close to a .4v drop.

What is the current load on the battery? North of 4 amps, or 3.8? I'm arguing with myself, going back and forth and can't remember much from all those EE classes in college.

 

[Sthur]

Found this from another forum.

Voltage drop under load explained well.

 

[Thrasher]

Found this from another forum.

Voltage drop under load explained well.

I still think joe ripped jay off on the price for the roller though........................



Ohm's Law Calculator
would be 3.8

one thing left out of these types of equations is voltage sag of the battery. but just assuming 4 would always be a safe bet. when I build a coil and calculate wattage I always assume it will be 4.2v at full charge even though it will almost never be that once the battery is under load and sags