The noise phenomena arranged in the order of their dominance when plotted as a function of increasing frequency are:

Noise Phenomena in Electronics

Noise phenomena in electronics refer to the unwanted disturbances or random fluctuations that interfere with the desired signal in electronic circuits and systems. These phenomena are categorized into different types based on their frequency characteristics and sources, such as flicker noise, white noise, and transit time noise.

Correct Option: The noise phenomena arranged in the order of their dominance when plotted as a function of increasing frequency are:

Option 2: Flicker noise, White noise, Transit time noise

This sequence correctly explains how different noise phenomena dominate over specific frequency ranges. Let's delve into the explanation for each type of noise to understand why Option 2 is correct:

1. Flicker Noise (1/f Noise):

• Flicker noise is most dominant at low frequencies. It arises due to imperfections in the electronic devices, such as fluctuations in the mobility of charge carriers, or irregularities in material properties.
• The power spectral density (PSD) of flicker noise is inversely proportional to frequency (1/f). As frequency increases, the dominance of flicker noise diminishes.
• Flicker noise is a key concern in low-frequency applications like precision amplifiers and audio systems.

2. White Noise:

• White noise is frequency-independent and has a constant power spectral density over a wide range of frequencies.
• It originates from thermal agitation of charge carriers (thermal noise) or quantum effects (shot noise).
• At intermediate frequencies, white noise dominates as flicker noise decreases with increasing frequency, and transit time noise has not yet become significant.

3. Transit Time Noise:

• Transit time noise becomes significant at very high frequencies, often in the gigahertz range, and is associated with the finite time it takes for charge carriers to traverse a semiconductor device.
• It is proportional to the frequency and becomes a limiting factor in the performance of high-frequency devices like microwave transistors and high-speed amplifiers.

Conclusion: When plotted as a function of increasing frequency, flicker noise dominates at low frequencies, white noise dominates at intermediate frequencies, and transit time noise becomes significant at very high frequencies. This sequence is captured accurately in Option 2: Flicker noise, White noise, Transit time noise.