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# Diode in circuit Watch

1. Yo people a quick question,

As you know, a diode only conducts if the pd across it exceeds 0.6V so...

The diode is placed in the forward direction in series with a 1.5V cell and a 2.2k resistor.

The question asks for the pd in the resistor...

Would it simply be 1.5 - 0.6 = 0.9V?

thnks
2. If it has to exceed 0.6V then pd has to be less than 0.9V. But yeah your answer is fine enough
3. V(diode) + V(resistor) = 1.5

V(resistor) = 2.2k times I

V(diode) = diode formula (which you should have been given) times I

So diode formula + 2.2K = 1.5/I

so now you have the current going through the circuit. From that you can work out the pd across the resistor.

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