Calculating Planck's constant from LED experiment.

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The discussion focuses on calculating Planck's constant using an LED experiment, highlighting that the I-V curve of the circuit is not linear at low bias voltages. It emphasizes the importance of knowing the power output of the LED to backtrack to Planck's constant (h) using the equation E = hν. Assumptions about the conversion efficiency of electrical power to light versus heat are crucial for accurate calculations. Participants suggest consulting the LED datasheet for relevant information to aid in these calculations. The conversation underscores the need for careful consideration of variables in the experiment.
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edit: problem solved. Thankyou berkeman.
 
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The I V curve of that circuit should not be linear, at least not for the first few volts of bias.

You will have to make some assumptions, but if you know the power of the light that comes out of the LED, you can work back to h.

http://en.wikipedia.org/wiki/Planc's_constant

Do you have some ideas about how you can use this equation?

E = h \nu

I'm not sure what you should do about the assumption of how much of the power delivered to the LED (excluding the external dropping resistor of course) is converted to light, versus heat. Do you have the datasheet for the LED? That may give you that part of the calculation.
 

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