Looking for capacitive reactance but missing "C"

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The discussion revolves around calculating capacitive reactance (Xc) in a capacitor circuit with a frequency of 1000Hz. The formula for Xc is identified as Xc = 1/(2πƒC), but the challenge lies in determining the capacitance (C), which is not provided. Participants suggest obtaining reactance from current and voltage graphs, with one user successfully calculating Xc as 100Ω using voltage and current values. There is also a clarification needed on the proper notation for current measurements. The conversation emphasizes the importance of having all necessary parameters to solve for capacitive reactance accurately.
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1. Current and voltage graphs are shown for a capacitor circuit with ƒ=1000Hz.
What is the capacitive reactance Xc?




2. I know the equation is Xc= 1/2∏ƒC to solve for capacitive reactance but where do I find C? All of our in class examples had C and ƒ given.



The Attempt at a Solution

 

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tessie0407 said:
2. I know the equation is Xc= 1/2∏ƒC to solve for capacitive reactance
That formula is not correct. You need a pair of brackets to set it right or you'll never get the right answer!

What would be the equation for current if you connect that capacitance C to an AC voltage source V volts?
 
tessie0407 said:
1. Current and voltage graphs are shown for a capacitor circuit with ƒ=1000Hz.
What is the capacitive reactance Xc?

2. I know the equation is Xc= 1/2∏ƒC to solve for capacitive reactance but where do I find C? All of our in class examples had C and ƒ given.

The Attempt at a Solution


Get the reactance from the graph.


What are peak voltage & peak current?
 
The only other thing I can think to do is rearrange ΔVc= I*Xc

Xc= ΔVc/I
Xc= 10V/10x10^-2 A which gives me 100Ω
 
tessie0407 said:
The only other thing I can think to do is rearrange ΔVc= I*Xc

Xc= ΔVc/I
Xc= 10V/10x10^-2 A which gives me 100Ω
10V looks right for the voltage. But that's not the right way to write 10mA.
 
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