Hi need answer to question 2 The circuit diagram shown here is partially complet

Question

Hi need answer to question 2

The circuit diagram shown here is partially complete. The sketch of the output voltage Vo is shown here with a -15 V DC offset. Complete the circuit the circuit diagram by adding the element (or elements) needed to produce the output shown (be careful with the polarity). What can you conclude about the peak-to-peak voltage (based on the scale for 15 V)? what is the approximate frequency if Omega = 0.105 radians per second? Identify the circuit, i.e LPF or HPF. Sketch the Bode plot for this circuit showing the cutoff frequency and its d8 value, Describe what happens in the low frequency and high frequency regime to the voltage at the output, i.e. across the capacitor.

Explanation / Answer

It is an LPF.

Look at the circuit in this way: If the output voltage is given by the voltage partition between the resistor and the capacitor. The impedance of the resistor in constant, while that of the capacitor is

ZC=1/jC

Notice as ,ZC0. So the capacitor behaves like a short circuit for really high frequencies. We call this a "high pass filter" because it lets the high frequency signals through.

What about low frequencies you say? As 0,ZC. So the capacitor will behave like an open circuit. This means zero current will flow through the circuit, and hence the voltage across the resistor is zero. So the resistor also behaves like a short circuit. Notice no low signal frequencies can get through.

This is why we call it a high pass filter. It lets the high frequency signals pass, and low ones get blocked.

If you reverse the order of the resistor and capacitor in the circuit, you obtain a low pass filter.

A useful way to easily remember which filter is which, is to remember these:
CR - High pass filter
RC - Low pass filter
Where the order of the letters actually tells you the order of the components in the circuit.

I think I have answered Part 1 & 3 for you.

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