Sounds like you have found a good read....[worst whiny little kid tone you can think of] can I borrow it?There is a reason why I did not vote down your post, because you were right despite your aggressiveness. I am not here to make enemies. I realize I am sometimes overconfident in my knowledge.
As for you question, the theoretical voltage and current limitations of a 1 Megaohm, 1/4 W resistor are 500 V and 0.5 mA respectively. Of course, that is without knowing the tolerance so the resistor could be destroyed before reaching said limitations. Dielectric breakdown could be an issue to consider as well with that high of voltage. I think I know what you are getting at though. 1 Megaohm is about the resistance of a human with dry skin.
I found an interesting book on electrical stimulation called "Electrical Stimulation and Electropathology," that would definitely prove useful in this area. I have not been able to read it, but I took a good look at the table of contents and decided I wanted it.
Back to the limitations of the resistor from Radio Shack...and 1 MegOhm was chosen for ease of calculation, you can get your digital meter to read around 15K if you squeeze the probe tips hard with your fingers.
What do you think the likely tolerance on the resistance actually is? And what do you think happens if you dissipate just a hair more than 1/4W in a 1/4W resistor? (I encourage you to actually get a similar resistor, and to get one around 1K, and measure the actual resistance and dissipate a hair more than 1/4W in it. You already have the adjustable power supply, and the meter is useful occasionally for household and automotive jobs; it's under $20 at "The shack".
