Internal resistance of LDo

I was trying to measure the internal resistance of an LDO that will produce 2.85V. I used a Digital multimeter to do this, but I got a resistance of 810 Ohm and the LDO can support upto 450 mA. Will the internal resistance of the LDO can be that high?...Read more

Finding the Internal Resistance of an Ammeter using a shunt

There is this lab procedure to determine the internal resistance of an ammeter which differs from the usual process. In this new procedure, we connect a voltage supply in series with a resistor of some known value and an analog ammeter (top image). We increase the voltage until the ammeter reads 30mA and then turn off the supply. Then we add a shunt (a wire) in parallel to the ammeter (bottom image). We now use this setup and determine the internal resistance through some calculations using the formula shown in the image. I am not sure why...Read more