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An LED has a forward voltage drop of 2.25 V. As seen in the figure, it...

An LED has a forward voltage drop of 2.25 V. As seen in the figure, it is in series with: an AC source of V(t)=V0sin(2πft) with V0= 4.00 V, f=1 Hz, and a resistor R= 200 Ω

d. The whole flash:
1) If you were watching the LED, you would see it turn on and off with a period of 1s. During the 1s period, compute how long the LED is on (the time Δt of each pulse).
2) How much light energy is emitted during the entire LED light pulse? Hint: you first need to find the total photons emitted during the whole light pulse.

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genius_generous answered 2 years ago
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