Speed of Photons in Vacuum – Rankers Physics

Photoelectric Effects and deBroglie Equation: Practice Problem & Solution

The speed of photons of radiation having wavelength \(\lambda\), in vacuum is proportional to
\(\lambda\)
\(\lambda^0\)
\(\lambda^{-1}\)
\(\lambda^{1/2}\)

Solution Explained:

To solve this problem, we apply the core principles of Photoelectric Effects and deBroglie Equation. Understanding the underlying formula is key to arriving at the correct answer below:

In vacuum, the speed of all photons (electromagnetic waves) is constant (\(c = 3 \times 10^8 \text{ m/s}\)), which is independent of their wavelength. Thus, speed is proportional to \(\lambda^0\).

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