# I want to demo Ohms Law using LED, Power source and Resistor

#### jobitjoseph1

Joined Mar 22, 2018
3
Hi,
I am helping my niece with homework, she has to simulate the Ohm's law circuit. Basically a simple circuit with LED, resistor, and power source.
she can use any online simulation tool but it has to show the voltage drop across each component and prove that ohms law is being applied

The closest online ohms law tool i can find online is https://circuitdigest.com/calculators/ohms-law-calculator

But the simulartion value does not seem to change in this tool while change the voltage and resistor value. Can anyone point me towards the right tool?

#### ericgibbs

Joined Jan 29, 2010
18,835
Hi job,
The Amp meter in your simulation has zero resistance, so the voltage across the R1 and R2 resistors will always be 12V.

Try using two resistors in Series, add a resistor to the amp meter path.

E

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#### MrChips

Joined Oct 2, 2009
30,790
I don’t see any problems with your simulation except set the ammeter to show mA instead of A.

Use this Ohm’s Law formula,
I = V / R

#### ericgibbs

Joined Jan 29, 2010
18,835
But the simulartion value does not seem to change in this tool while change the voltage and resistor value.
Hi,
There is a problem with his set-up if, as he says, he is measuring voltage.
E

#### WBahn

Joined Mar 31, 2012
30,034
The instructions appear to require the use of an LED in the circuit, yet I don't see one.

#### MrChips

Joined Oct 2, 2009
30,790
Ohm's Law states that the current I through a resistance R is proportional to the voltage V across the resistor and inversely proportional to the resistance.

Stated mathematically,
I = V / R

I is the dependent variable.
V and R are independent variables.

V = I x R
is a corollary of Ohm's Law.

#### Alec_t

Joined Sep 17, 2013
14,312
But the simulartion value does not seem to change in this tool while change the voltage and resistor value.
The current value changes, as shown by the Ammeter readings.

#### BobTPH

Joined Jun 5, 2013
8,932
Yes, the circuit demonstrates Ohm’s law. Why someone thought an LED was of any use in doing so is beyond me.

The voltage does not change because the voltage you are measuring with that setup is the battery voltage.

#### crutschow

Joined Mar 14, 2008
34,392
Add an LED and another resistor in series.
Measure the current and the voltage across all the components.

#### Papabravo

Joined Feb 24, 2006
21,225
Don't expect the LED to follow Ohms law.