how big/ what kinda of resistor would i need to equal one 194 bulb?

i have an idea in store and need the car to think there's a bulb there, but not actually have one there.

 

Could just get a variable, and adjust it till it recognizes it. In case nobody really knows.

 

if you have a OHM meter, take the reading across the bulb.. and buy a resistor closest to what you got.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Oh Crap &raquo;</TD></TR><TR><TD CLASS="quote">if you have a OHM meter, take the reading across the bulb.. and buy a resistor closest to what you got. </TD></TR></TABLE>Light bulbs change their resistance quite a bunch when they're turned on. (The filament gets real hot...)

I don't know the wattage of a #194, but the resistance is V^2 / P. So....

If it's 10 watts @ 12 volts, then:

144 / 10 = 14.4 ohms.

 

Well, you can also turn on the light, wait for the bulb to get hot.. then remove the bulb to take the reading (while it's hot), just make sure not to burn yourself.

Yeah resistant changes with temperature.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Oh Crap &raquo;</TD></TR><TR><TD CLASS="quote">Well, you can also turn on the light, wait for the bulb to get hot.. then remove the bulb to take the reading (while it's hot), just make sure not to burn yourself.

Yeah resistant changes with temperature.</TD></TR></TABLE>LOL! We're not talking about the temperature of the glass envelope...

If you ignore non-grey emmissivity, the filament is probably around 2500 kelvins, which is about 4000 degrees F. It takes about 1/10 second to cool down below 1000deg.F, where it's not glowing any more. That's where the BIG change in resistance comes from. If you don't wanna calculate it based on wattage, just measure current when it's turned on. That's not rocket science...

 

Okay, I know we're not talkinga bout the glass envelope. I was referring to the measurements across the terminals of the bulbs. Measuing current would just be too much of a hassal, since you would need an ammeter + splice the wire to measure the current. But my best bet is to take an ohm-reading across the bulb at it's normal state (off). When you apply voltage to the resistor, it'll increase just like how the bulb would.. So IMO you're safe with that.