power calculation verification

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Joe G

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could someone double check to see if i calulated these two power measurements correctly. and if not could you show me the correct calculations, any help would be greatful. it's been a while, and i'm trying to relearn these things.
 
The LED power calculation is correct for the current you show. The regulator dissipation value you have includes the power in the 50Ω resistor. You need to subtract the resistor dissipation from your calculated value to get the regulator dissipation.

Incidentally, the constant current from the regulator through the LED is closer to 1.2/5 = 240mA rather than the 200mA you show since the regulator reference voltage is about 1.2V
 
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