Reposting my question from General Chat
Copper has one valence electron, with a density of 8.94 grams per cubic centimeter and an atomic weight of approximately 64 grams per mole. Suppose a copper wire has a current density of 18.8 amperes per square millimeter. Find the drift velocity inside the wire.
Determine the output voltage as a function of the source voltage, R1, and R2.
A note on studying for op amps and also a bit of a hint: Ideally, inverting and non-inverting op amp configurations should be memorized/included on your notes, but it's always good to be able to derive these formulas using basic circuit laws and the ideal op amp assumptions since it's really easy to create an op amp circuit that does not fall neatly into a standard configuration.
Close! Check the KCL expression again (and remember that I = V/R)Determine the output voltage as a function of the source voltage, R1, and R2.
A note on studying for op amps and also a bit of a hint: Ideally, inverting and non-inverting op amp configurations should be memorized/included on your notes, but it's always good to be able to derive these formulas using basic circuit laws and the ideal op amp assumptions since it's really easy to create an op amp circuit that does not fall neatly into a standard configuration.
- Interesting introduction problem to op-amps for me!
Whoops. I always mess up Ohm's law for some reason (I should really make sure to double check).Close! Check the KCL expression again (and remember that I = V/R)
Looks good!Whoops. I always mess up Ohm's law for some reason (I should really make sure to double check).Close! Check the KCL expression again (and remember that I = V/R)
- Take two
All right, thanks!Your turn!
- A neat little trick...
All right, thanks!
Onto basic circuit safety:
Touching two nodes of a DC voltage of above approximately what voltage can be lethal? What kind of factors affect whether a shock might be lethal? What current range is usually lethal? What are some harmful effects of having a current flow through you that is below the lethal limit (i.e. not enough to get you killed)?
Correct! Although, it's important to note that for current to happen, you do need a voltage. That's why you see signs like "High Voltage" on fences. The rule that current not voltage kills isn't entirely true because of this and is only a guideline. Be very wary of voltage, as it's impossible to know the resistance of your body at any given moment.All right, thanks!
Onto basic circuit safety:
Touching two nodes of a DC voltage of above approximately what voltage can be lethal? What kind of factors affect whether a shock might be lethal? What current range is usually lethal? What are some harmful effects of having a current flow through you that is below the lethal limit (i.e. not enough to get you killed)?
- Answer
Write the voltage drop equations for a capacitor and a resistor.
Awesome! You next.Write the voltage drop equations for a capacitor and a resistor.
Awesome! You next.Write the voltage drop equations for a capacitor and a resistor.
All right!Awesome! You next.Write the voltage drop equations for a capacitor and a resistor.
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.All right!
Describe the behavior of an RC circuit which is a) charging and b) discharging.
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