# induction/capacitance

Discussion in 'Homework Help' started by izaiyoi, Jan 28, 2008.

1. ### izaiyoi Thread Starter New Member

Nov 30, 2007
3
0
The ac voltage v(t) =10sin(100pt) is applied separately across (i) and (ii) below:
(i) a 1H inductor.
(ii) a 1mF capacitor

What are the frequency and rms values of the currents that flow in each instance?

2. ### mik3ca Active Member

Feb 11, 2007
189
0
If you have a capacitor connected with the inductor, the frequency can be determined by:

1 / (2 * pi * sqr(L * C))

sqr = square root of.

L = inductor value in Henries
C = capacitor value in farads
result = frequency in Hertz
pi = the Pi button on your calculator.

this might not help much, but it determines a frequency based on a capacitor and inductor connected to each other.

3. ### Dave Retired Moderator

Nov 17, 2003
6,960
145
If I write v(t) =10sin(100pt) is equivalent to v(t) =Asin(2πft), can you draw an equivalence for the frequency? (I'm not sure what "p" is from your equation for the voltage).

As for current you need to consider the current equations for:

An Inductor: v(t) = L(di(t)/dt)

A Capacitor: i(t) = C(dV/dt)

A bit of differentiation and the fact that the RMS current can be calculated by: I(rms) = I(peak)/√2 and you are there.

Dave