Electronic – Using multiple resistors on a breadboard to limit voltage to LED

breadboardledresistors

so I've recently begun my venture into electrical engineering, just got myself a breadboard with some jumper cables, a pack of assorted LED's and a few 200 ohm resistors.

I'm trying to understand how to further limit voltage to my LED using a 9V battery and multiple 200 ohm resistors but I've come up with the following question / problem.

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Judging from this image: can you please tell me if this is wired properly? I have 7 200 ohm resistors connected in this circuit and it doesn't appear to be dimming the LED at all. When I take away 3-4 resistors, it's still just as bright. @ 1400 ohms, I figured the LED's would be significantly dimmer but alas they're not.

The specification of the LED i'm trying to power with my 9V battery is, Green, 2.9-3.1V with a forward voltage of 20mA

Anyhow, I'm having a heck of a time tying to wrap my head around this and figure it's something small I'm missing. When I touch all 7 resistors connected to this circuit, I can definitely feel a significant amount of heat coming off of them.

Would anyone be able to assist me with this issue I'm having? any advise or criticism is appreciated.

Thanks all.

Best Answer

First of all, lovely picture. This makes it easy for me to see what's going on.

Looks like you are adding the resistors in parallel and so each additional one is reducing the total resistance.

Try hooking them in series instead and you should see the LED get dimmer.

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