Is the Formula for Voltage Drop Across Capacitor Opposite of Resistor?

AI Thread Summary
The discussion centers on calculating the voltage drop across capacitors in series, specifically a 60uF and a 30uF capacitor powered by 60V. It questions whether the formula for voltage drop across capacitors is the opposite of that for resistors, highlighting confusion over the correct equations. The key point is that in series, equal amounts of charge are stored in each capacitor, and the relationship between charge (Q), capacitance (C), and voltage (V) should be used to derive the correct formulas. The conversation emphasizes the importance of understanding these relationships rather than relying solely on potentially incorrect formulas. Overall, clarity in deriving the equations is essential for accurate calculations.
Joel Kee
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Homework Statement


I'm trying to calculate the voltage drop across a 60uF and a 30uF capacitor in series, powered by 60V. Is the formula for voltage drop across capacitor opposite of the formula for resistor, where resistor is R1=R1/(R1+R2) while capacitor is C1=C2/(C1+C2)?

Homework Equations

The Attempt at a Solution

 
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Joel Kee said:
Is the formula for voltage drop across capacitor opposite of the formula for resistor, where resistor is R1=R1/(R1+R2) while capacitor is C1=C2/(C1+C2)?
The symbols on the left side don't make sense. The right side is useful, but you should probably derive those equations to be sure.
 
mfb said:
The symbols on the left side don't make sense. The right side is useful, but you should probably derive those equations to be sure.
My bad, the eqs are supposed to be multiplied with the total voltage.
 
It is far better that you be confident at deriving such formula yourself using basic knowledge.

The crux of the matter is that when connected to a source, equal amounts of charge are added to each of the series-connected capacitors.
Use this fact, together with Q = C·V, to confirm or disprove the formula you wrote.
 
Joel Kee said:
My bad, the eqs are supposed to be multiplied with the total voltage.
Still your bad. R1=R1/(R1+R2) ? Etc.
 
rude man said:
Still your bad. R1=R1/(R1+R2) ? Etc.
V1=[R1/(R1+R2)]V

My bad.
 

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