Re: Basic question about volts

From: mike c (mikechambersATgmail.com)
Date: 12/30/04 

Date: Thu, 30 Dec 2004 09:59:27 -0800

Thanks. That helps clarify things.

One more questions. If I have multiple LEDs, can they all use the same
resistor?

i.e. the 5 volt wire comes in, and has a resistor connected to it. Then
multiple LEDs are connected to the resistor, and the each LED is
connected to the ground.

Is that possible? Is this running the LEDs in Parellel?

mike c

John Popelish wrote:

> passing the needed current. Typically, this is a resistor. Ohm's law
> relates resistance, voltage drop and current. If you wanted .01
> ampere (10 milliamps) to pass through both the resistor and LED, while
> the LED dropped 2 volts, but your power supply supplied 5 volts, you
> would need a 300 ohm resistor in series with the LED so that it would
> drop 3 volts while passing .01 ampere (because 3 volts divided by .01
> ampere = 300 ohms).

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