# What is the reactance (Xc) of a 300 pF capacitor at 30 KHz? How do I work this problem?

I know to find Xc you do 1/2(pie)(f)(c) but I can't figure out how to find the C part of the equation. Any suggestions?

Relevance

The other 2 responders are correct. The full solution of your problem is as follows, when you use mf as the capacitance. mf is the normal value for most calculations, since a farad is a large value in electronics. But, you can use the capacitance expressed as farads, in the formula below, by replacing the last factor (C/1000000) with the equivalent value expressed as farads.

300 pf is 0.0003 mf

Use the following formula XC = 1 / (2 * Pi * F * (C / 1000000))

where

C=capciyance in mf

F=30000

XC is ohms.

TexMav

• Login to reply the answers
• C is the capacitance in farads. Specifically, 300 pF in the specification of your problem

• Login to reply the answers
• 1 pF=1x10^-12 so 300 pF=300X10^-12 or 3x10^-10

• Login to reply the answers
• C = 300e-9

• Login to reply the answers