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Derive the expression for the RMS pressure of a square wave and a triangular wave. Compare the value of the RMS pressure for sinusoidal, square and triangular waves. Assume all three waves have the same period and amplitude and all have zero mean values

User Crusy
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Answer:

Step-by-step explanation:

The Root Mean Square (RMS) pressure of a waveform can be defined as the square root of the average of the square of the pressure values over one period of the wave. The RMS pressure provides a measure of the effective pressure of a waveform and is often used to compare the strength of different waveforms.

For a square wave, the RMS pressure can be found as follows

P_RMS = sqrt((1/T) * ∫_0^T (P_square(t))^2 dt)

Where T is the period of the waveform and P_square(t) is the pressure value of the square wave at time t. The integral is taken over one period of the waveform.

For a triangular wave, the RMS pressure can be found as follows:

P_RMS = sqrt((1/T) * ∫_0^T (P_triangular(t))^2 dt)

Where T is the period of the waveform and P_triangular(t) is the pressure value of the triangular wave at time t. The integral is taken over one period of the waveform.

The RMS pressure of a sinusoidal wave is given by the equation:

P_RMS = (A/sqrt(2))

Where A is the amplitude of the waveform.

Comparing the RMS pressures of the three waveforms, it can be seen that the RMS pressure of a sinusoidal wave is (A/sqrt(2)) which is smaller than the RMS pressure of a square wave or a triangular wave. This is because the square wave and triangular wave have sharper transitions from positive to negative values compared to the sinusoidal wave, which results in higher peak pressure values and hence a higher RMS pressure.

It is worth noting that while the RMS pressures of the three waveforms are different, they provide a measure of the effective pressure of the waveforms and can be used to compare their strengths.

Here is a definition of each variable used in the equation:

P_RMS: The Root Mean Square (RMS) pressure of the waveform. It is a measure of the effective pressure of the waveform.

T: The period of the waveform. It is the time it takes for the waveform to repeat itself.

P_square(t): The pressure value of the square wave at time t.

P_triangular(t): The pressure value of the triangular wave at time t.

∫_0^T: The integral symbol. It represents the sum of the pressure values over one period of the waveform, from time t = 0 to time t = T.

A: The amplitude of the waveform. It is the maximum positive or negative deviation from the zero line of the waveform.

sqrt: The square root symbol. It is used to find the square root of a value.

(A/sqrt(2)): The RMS pressure of a sinusoidal wave. It is calculated as the amplitude divided by the square root of 2.

User Vinodkone
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