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## Main Question or Discussion Point

Hello again, I am trying to knock out some challenge questions in my text (to prepare for my midterms) and I came across this question.

A 10V, 2.5kHz, sine wave is applied to a series combination of a 0.01µF capacitor and a 10kΩ resistor. What would the total current be?

The answer in the back of the book says 0.844mA

I am not getting anything anywhere near that. Can someone please tell me where I am thinking incorrectly? Thanks.

Here is my thought process.

First, calculate the capacitive reactance: 1/2πfC = 1/(2πx2500x0.1x10^-6) = Xc = 6366.2Ω

This is where I think I am going wrong.

since the capacitor and the resistor are in series, so i added the capacitive reactance and resistance together: 6366.2 + 10,000 = 16,366.2Ω

I then applied ohm's law to get 10/16366.2 = 0.611mA which is way off

Using backwards design, I figured 10/0.844mA = 11,848Ω

which means that in some way shape or form, my total resistance in the circuit should be 11848Ω

I cannot figure out how to get my Xc of 6366.2Ω and resistor 10k to combine in a manner that would be 11848Ω

Any insight would be great!

Thanks!

A 10V, 2.5kHz, sine wave is applied to a series combination of a 0.01µF capacitor and a 10kΩ resistor. What would the total current be?

The answer in the back of the book says 0.844mA

I am not getting anything anywhere near that. Can someone please tell me where I am thinking incorrectly? Thanks.

Here is my thought process.

First, calculate the capacitive reactance: 1/2πfC = 1/(2πx2500x0.1x10^-6) = Xc = 6366.2Ω

This is where I think I am going wrong.

since the capacitor and the resistor are in series, so i added the capacitive reactance and resistance together: 6366.2 + 10,000 = 16,366.2Ω

I then applied ohm's law to get 10/16366.2 = 0.611mA which is way off

Using backwards design, I figured 10/0.844mA = 11,848Ω

which means that in some way shape or form, my total resistance in the circuit should be 11848Ω

I cannot figure out how to get my Xc of 6366.2Ω and resistor 10k to combine in a manner that would be 11848Ω

Any insight would be great!

Thanks!