You CAN manipulate current directly, but of course it effects the voltage and/or the resistance according to Ohm's law. Example 1: Set your bench supply to deliver 100 mA through a 100 ohm resistor. Measure the voltage across the resistor and behold! V = IR = 10 volts. Example 2: Set your bench supply to deliver 10 volts through a 100 ohm resistor. Measure the current, and I = V/R = 10/100 = 100mA Example 3: Imagine you could set your bench supply to output both a constant voltage and current, say 100mA and 10V. Then connect a wire between the output and ground. Upon making the connection, you would find the wire heats up to some temperature at which its total resistance to flow of current is 100 ohms. (never actually do this.. it would probably destroy your bench supply) So you see then that no single variable is always or never the dependent variable (which is what I think everybody has been saying all along?) ----- Original Message ----- From: "Rick Regan" To: Sent: Friday, April 16, 2004 10:50 AM Subject: Re: [EE]: Why isn't Ohm's Law written I=V/R? > > You can only change current by changing voltage or resiatnce, as per Ohms > > law! A bench supply in constant current mode simply adjusts voltage to > > achieve the desired current through an arbitrary resistance > > Well, we've come full circle, because that's what I said > in my original post. Since then, others appeared to have contradicted that, saying you can manipulate current > directly. > > -- > http://www.piclist.com hint: PICList Posts must start with ONE topic: > [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads