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Home Q & A Board Science-Related Homework Help Physics
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rkearl27 rkearl27
wrote...
Posts: 165
Rep: 1 0
11 years ago
The circuit in Q1 wastes energy ? as heat in R6. An alternative strategy is to use a switching
power supply, sold as being 90% efficient and it is used with no R6, feeding the LED directly. Calculate
the efficiency of the circuit in Q1, as the ratio of power delivered to the LED  to power wasted.

R6 = 527 Ohms

Just need to know the basic formula. Any help would be greatly appreciated

Thanks
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wrote...
#1
11 years ago
The efficiency of a circuit depends no more than just the power supply.  In order to properly drive an LED you must have something to regulate the diode current.  In order to determine the overall efficiency you need to show us your circuit.
wrote...
#2
11 years ago
the image A1 here has the answer to your question
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