- #1
Sarah88
- 14
- 0
Homework Statement
A 20 nF capacitor is connected across an AC generator that produces a peak voltage of 5.0 V.
- At what frequency f is the peak current 50 mA
- What is the instantaneous value of the emf at the instant when ic= Ic?
Homework Equations
Ic= C(2*pi*f*Vc)
Ic= Vc/Xc
Xc= 1/(2*pi*f*C)
possibly E= Eocos(2*pi*f*t)
The Attempt at a Solution
I understood the first part of the question and found the frequency to be 79365 Hz. I tried using this value with the equation Ic=C(2*pi*f*Vc) and solving for Vc (assuming Vc is emf) so : 50*10^-3 A= (20*10^-9 F) (2*pi* 79365 Hz*Vc) therefore Vc= 5 V. However, the answer to the problem is 0 and I'm not sure how that answer was obtained. Any hints, or useful equations would be great, thank you!