resistors

[Stevo]

Can 1/8 watt resistors be used in a 9volt system.....Havent had touble yet?...or an 18 volt system...... Thanks

[niftydog]

yes, but only if they remain under 1/8 of a watt! hell, you can use them in a 2,000V system, provided you keep them under 1/8W!

Take note of the red ones below and break out the calculator and multimeter!

Power (P, watts) = voltage x current
P = current squared x resistance
P = voltage squared / resistance

voltage = current x resistance
current = voltage / resistance
resistance = voltage / current

[Connoisseur of Distortion]

the way to test that is to put it across the lugs of a 9v battery  :wink:

(I'M KIDDING! IT'LL FRY!)   :shock:

[Hal]

the way to test that is to put it across the lugs of a 9v battery  :wink:

(I'M KIDDING! IT'LL FRY!)   :shock:

it'll fry if...


1/8=81/r

R < 648ohms

[niftydog]

Hals post assumes it has the full 9VDC voltage accross the resistor. Naturally, not every resistor in a circuit has the full power supply voltage across it. Hence the need for a multimeter and some calculations.

[Hal]

Hals post assumes it has the full 9VDC voltage accross the resistor. Naturally, not every resistor in a circuit has the full power supply voltage across it. Hence the need for a multimeter and some calculations.

I also assume 0 internal resistance...

and a resistor that is to spec...