## Circuit Lab B/C

UTF-8 U+6211 U+662F
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### Re: Circuit Lab B/C

All right!

Describe the behavior of an RC circuit which is a) charging and b) discharging.
a) The voltage through the resistor starts high and decays exponentially as the capacitor becomes saturated. The charged capacitor has an extremely high voltage drop.
b) The voltage through the resistor starts high and decays exponentially as the capacitor discharges. The capacitor acts as a voltage source in the absence of other sources.
Yep, your turn.

Jacobi
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### Re: Circuit Lab B/C

Do current and voltage sources exist in real circuits?

UTF-8 U+6211 U+662F
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### Re: Circuit Lab B/C

Do current and voltage sources exist in real circuits?
Not ideal ones but they can be approximated; however, real-life sources have a limited amount of charge (which can be measured in ampere-hours) and have internal resistance that sometimes needs to be accounted for.

Jacobi
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### Re: Circuit Lab B/C

Do current and voltage sources exist in real circuits?
Not ideal ones but they can be approximated; however, real-life sources have a limited amount of charge (which can be measured in ampere-hours) and have internal resistance that sometimes needs to be accounted for.
Right! Your turn.

UTF-8 U+6211 U+662F
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### Re: Circuit Lab B/C

What is doping in the context of PN junctions and why is it done?

mdv2o5
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### Re: Circuit Lab B/C

What is doping in the context of PN junctions and why is it done?
Answer

UTF-8 U+6211 U+662F
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### Re: Circuit Lab B/C

What is doping in the context of PN junctions and why is it done?
Answer
Yep, your turn!

mdv2o5
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### Re: Circuit Lab B/C

Calculate the RMS voltage of a 12V peak-to-peak sinusoidal AC signal and a 0-6V square wave with a time-on of 8ms and a period of 10 ms.

UTF-8 U+6211 U+662F
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### Re: Circuit Lab B/C

Calculate the RMS voltage of a 12V peak-to-peak sinusoidal AC signal and a 0-6V square wave with a time-on of 8ms and a period of 10 ms.
$12\ V \cdot \frac{\sqrt2}{4} = 3\sqrt2\ V$

$\sqrt{\frac{8\ ms}{10\ ms} * (6\ V)^2} = 5.367\ V$

mdv2o5
Member
Posts: 19
Joined: July 9th, 2018, 7:24 am
Division: Grad
State: IN
Location: MA

### Re: Circuit Lab B/C

Calculate the RMS voltage of a 12V peak-to-peak sinusoidal AC signal and a 0-6V square wave with a time-on of 8ms and a period of 10 ms.
$12\ V \cdot \frac{\sqrt2}{4} = 3\sqrt2\ V$

$\sqrt{\frac{8\ ms}{10\ ms} * (6\ V)^2} = 5.367\ V$
Looks good!

UTF-8 U+6211 U+662F
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### Re: Circuit Lab B/C

All right! Derive an equation for the power given off by a resistor from Ohm's law.

Jacobi
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### Re: Circuit Lab B/C

All right! Derive an equation for the power given off by a resistor from Ohm's law.
My Answer

UTF-8 U+6211 U+662F
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### Re: Circuit Lab B/C

All right! Derive an equation for the power given off by a resistor from Ohm's law.
My Answer
Yep, your turn, although I was thinking of a derivation using
Definition
But that's a little more complicated (and equivalent).

Jacobi
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### Re: Circuit Lab B/C

Two resistors are combined in a circuit. First, they are combined in series. Then, they are combined in parallel. What is the equivalent single resistance of each setup?

UTF-8 U+6211 U+662F
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### Re: Circuit Lab B/C

Two resistors are combined in a circuit. First, they are combined in series. Then, they are combined in parallel. What is the equivalent single resistance of each setup?
$R_{series} = R_1 + R_2$
$R_{parallel} = \frac1{\frac1{R_1} + \frac1{R_2}}$

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