Question

1. If you connect a 9 v battery up to a 7 Ω resistor and a 10 μF capacitor for a very long time, what would the current in the circuit be?

2. What is the time constant in an RC circuit and how is it found?

3. In your own words what is meant by an RC circuit and give an example of one you might find in the real world.

Answer 1

1). Current, I = V/R = 9/7 = 1.286 A...

2). Time constant = R*C = 7 * 10*10^(-6) = 7.0*10^(-5) seconds.

3)...

RC Circuit

Definition: The combination of a pure resistance R in ohms and pure capacitance C in Farads is called RC circuit. The capacitor stores energy and the resistor connected in series with the capacitor controls the charging and discharging of the capacitor. The RC circuit is used in camera flashes, pacemaker, timing circuit etc.

The RC signal filters the signals by blocking some frequencies and allowing others to pass through it. It is also called first-order RC circuit and is used to filter the signals bypassing some frequencies and blocking others. The RC filters are mostly used for selecting signals and for rejecting noise.

The high-pass filter and the low-pass filter are the most common type of RC filters. The high pass filter passes the frequency greater than the fixed cut-off frequency and blocks the frequency lower than the fixed cut-off frequency.

Similarly, the low-pass filter allows the frequency lower than the fixed cut-off frequency and attenuates the frequency higher than the fixed cut-off frequency