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An indicator lamp on a panel is one LED, which glows… | StemPy Lab
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An indicator lamp on a panel is one LED, which glows well at 20 mA. When it conducts, there is 2.7 V across it. The panel has a 15 V line. What resistor in series with the LED sets the current at its working value?
Physics
Medium
High School (11–12)
Electronics
Created by
StemPy Lab
An indicator lamp on a panel is one LED, which glows well at
20
20
20
mA. When it conducts, there is
2.7
2.7
2.7
V across it. The panel has a
15
15
15
V line. What resistor in series with the LED sets the current at its working value?
885
Ω
885\ \Omega
885
Ω
750
Ω
750\ \Omega
750
Ω
615
Ω
615\ \Omega
615
Ω
135
Ω
135\ \Omega
135
Ω
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