How Much Lead?
If you know the ratio of capacitive reactance to resistance, or XC/R, in an RC circuit, then you can find the phase angle. Of course, you can find this angle if you know the...
Category: Capacitive Reactance
Capacitive Reactance
Current Leads Voltage
When ac is driven through a capacitor and starts to increase (in either direction), it takes a fraction of a cycle for the voltage between the plates to follow. Once the current starts decreasing...
Vectors in the RC Plane
Four points in the RC plane. Recall from the last topics that RL impedances can be represented as vectors. The same is true for RC impedances. In above figure, four different complex impedance points...
Points in the RC Plane
In a circuit containing resistance and capacitive reactance, the characteristics are two-dimensional in a way that is analogous to the situation with the RL plane from the previous topics. The resistance ray and the...
Capacitive Reactance and Frequency
In one sense, capacitive reactance behaves like a reflection of inductive reactance. But looked at another way, XC is an extension of XL into negative values. If the frequency of an ac source (in...
Capacitors and Alternating Current
Now, imagine that the voltage source connected across the plates is changed from dc to ac (following figure). Imagine that you can adjust the frequency of this ac from a low value of a...
Capacitors and Direct Current
CAPACITIVE REACTANCE IS THE NATURAL COUNTERPART OF INDUCTIVE REACTANCE. IT, LIKE INDUCTIVE reactance, can be represented as a ray. The capacitive-reactance ray goes in a negative direction and is assigned negative ohmic values. When...